{"title":"Blocks","description":null,"products":[{"product_id":"ronstan-series-30-utility-ball-bearing-block-single-swivel-shackle-head-rf30100","title":"Ronstan Series 30 Utility Ball Bearing Block, Single Swivel Shackle Head RF30100","description":"\u003cp\u003e\u003cstrong\u003eSeries 30 Utility Ball Bearing Block - Single, Swivel Shackle Head\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eLow friction 2-stage ball bearing system provides consistent performance over the full working load range.\u003c\/li\u003e\n\u003cli\u003eHigh static and dynamic load capacity.\u003c\/li\u003e\n\u003cli\u003eLight weight\u003c\/li\u003e\n\u003cli\u003eVersatile head fittings\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eProduct Information:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eSheaves running on Acetal or Torlon ball bearings provide high performance  low friction. The 2-stage ball bearing system provides consistent performance over the full load range.Can be fitted with a shackle in either of two planes to allow correct alignment of the block.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003ePrimary lead blocks on dinghies and catamarans\u003c\/li\u003e\n\u003cli\u003eControl lines on larger yachts\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU.V. stabilized Acetal sheaves\u003c\/li\u003e\n\u003cli\u003eAcetal ball bearings\u003c\/li\u003e\n\u003cli\u003eImpact modified, fiber reinforced and U.V. stabilized Nylon cheeks\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel load straps and head fittings\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 30 Utility Ball Bearing Block RF30100\u003c\/strong\u003e is a lightweight, single-sheave sailing block designed for reliable control-line handling on dinghies, catamarans, and larger yachts. Its low-friction, two-stage ball-bearing system supports consistent performance throughout the working load range, helping sailors manage primary lead blocks and control lines with smooth, dependable operation.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe swivel shackle head provides versatile rigging options and can be fitted in either of two planes to help maintain proper block alignment. This adaptable design is useful when line direction changes during sailing or when hardware positioning requires flexible alignment. The block combines a high static and dynamic load capacity with a lightweight construction suited to a broad range of marine applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFeature: Low-friction two-stage ball-bearing system provides consistent performance across the working load range.\u003c\/li\u003e\n\u003cli\u003eFeature: High static and dynamic load capacity supports demanding sailing applications.\u003c\/li\u003e\n\u003cli\u003eFeature: Swivel shackle head can be fitted in either of two planes for correct alignment.\u003c\/li\u003e\n\u003cli\u003eFeature: Lightweight construction is suitable for primary lead blocks and control lines.\u003c\/li\u003e\n\u003cli\u003eFeature: Versatile head fittings accommodate flexible rigging arrangements.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBrand: Ronstan\u003c\/li\u003e\n\u003cli\u003eSeries: 30 Utility\u003c\/li\u003e\n\u003cli\u003ePart number: RF30100\u003c\/li\u003e\n\u003cli\u003eProduct type: Single utility ball bearing block with swivel shackle head\u003c\/li\u003e\n\u003cli\u003eSheaves: UV-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003eBearings: Acetal ball bearings\u003c\/li\u003e\n\u003cli\u003eCheeks: Impact-modified, fiber-reinforced, UV-stabilized Nylon\u003c\/li\u003e\n\u003cli\u003eLoad straps and head fittings: Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003eApplications: Primary lead blocks on dinghies and catamarans; control lines on larger yachts\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan Series 30 Utility Ball Bearing Block RF30100 for a versatile, low-friction sailing hardware solution built around reliable alignment and proven marine materials.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Shop the Ronstan Series 30 Utility Ball Bearing Block RF30100 with low-friction bearings, swivel shackle head, and versatile sailing applications.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLow-friction two-stage ball-bearing system provides consistent performance across the working load range.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eHigh static and dynamic load capacity supports demanding sailing applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSwivel shackle head can be fitted in either of two planes for correct alignment.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLightweight construction is suitable for primary lead blocks and control lines.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eVersatile head fittings accommodate flexible rigging arrangements.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881641275481,"sku":"72397","price":46.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/72397XL.jpg?v=1789190365"},{"product_id":"ronstan-rf285-series-30-utility-block-cheek-curved-base","title":"Ronstan RF285 Series 30 Utility Block – Cheek, Curved Base","description":"\u003cp\u003e\u003cstrong\u003eSeries 30 Utility Block- Cheek, Curved Base\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eLightweight durable construction\u003c\/li\u003e\n\u003cli\u003eEconomical\u003c\/li\u003e\n\u003cli\u003eMaintenance free\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eProduct Information:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eStainless steel cheeks and Acetal sheaves ensure a long service life with virtually no maintenance.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eVang, cunningham and trapeze retriever systems on dinghies\u003c\/li\u003e\n\u003cli\u003eLeech line tackles, bunk adjusters etc on larger yachts\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU.V. stabilized Acetal sheaves\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF285 Series 30 Utility Block – Cheek, Curved Base\u003c\/strong\u003e is a lightweight, durable pulley block for dinghy and larger yacht control systems. Built with Grade 316 stainless steel cheeks and U.V.-stabilized Acetal sheaves, this utility block provides long service life with virtually no maintenance. Its curved-base cheek design makes it a practical choice for compact rigging applications where dependable line handling and economical construction matter.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eUse the Ronstan Series 30 Utility Block for vang, cunningham, and trapeze retriever systems on dinghies. It is also suited to leech line tackles, bunk adjusters, and similar applications on larger yachts. The combination of stainless steel cheeks and Acetal sheaves supports reliable use in marine rigging environments while helping reduce maintenance requirements over the life of the block.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Lightweight durable construction\u003c\/strong\u003e supports practical installation and dependable everyday use in marine control systems.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Economical design\u003c\/strong\u003e provides a cost-conscious option for a variety of dinghy and yacht rigging applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Maintenance-free operation\u003c\/strong\u003e helps minimize routine upkeep during normal use.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: U.V.-stabilized Acetal sheaves\u003c\/strong\u003e are designed for long service life in the specified applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Grade 316 stainless steel cheeks\u003c\/strong\u003e provide the specified durable cheek construction.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e RF285\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 30 utility block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e Cheek with curved base\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave material:\u003c\/strong\u003e U.V.-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek material:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntended applications:\u003c\/strong\u003e Vang, cunningham, and trapeze retriever systems on dinghies; leech line tackles and bunk adjusters on larger yachts\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF285 Series 30 Utility Block for a straightforward, durable solution to supported dinghy and yacht rigging applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO META DESCRIPTION:\u003c\/strong\u003e Shop the Ronstan RF285 Series 30 Utility Block with curved base, Acetal sheave, and Grade 316 stainless steel cheeks for marine rigging.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLightweight durable construction supports practical installation and dependable everyday use in marine control systems.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eEconomical design provides a cost-conscious option for dinghy and yacht rigging applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eMaintenance-free operation helps minimize routine upkeep during normal use.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eU.V.-stabilized Acetal sheaves are designed for long service life in the specified applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eGrade 316 stainless steel cheeks provide the specified durable cheek construction.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881642029145,"sku":"72300","price":42.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/72300XL.jpg?v=1789190635"},{"product_id":"ronstan-rf417-series-30-double-utility-block-with-tube-rivet","title":"Ronstan RF417 Series 30 Double Utility Block with Tube Rivet","description":"\u003cp\u003e\u003cstrong\u003eSeries 30 Utility Block- Double, Tube Rivet\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eLightweight durable construction\u003c\/li\u003e\n\u003cli\u003eEconomical\u003c\/li\u003e\n\u003cli\u003eMaintenance free\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eProduct Information:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eStainless steel cheeks and Acetal sheaves ensure a long service life with virtually no maintenance.Hollow rivets accept fixing screws, shackles or can be used as a becket for extra purchase.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eVang, cunningham and trapeze retriever systems on dinghies\u003c\/li\u003e\n\u003cli\u003eLeech line tackles, bunk adjusters etc on larger yachts\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU.V. stabilized Acetal sheaves\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF417 Series 30 Utility Block – Double, Tube Rivet\u003c\/strong\u003e is a lightweight, durable double block designed for practical sailboat and yacht control-line applications. Built for sailors, riggers, and boat owners, this economical utility block provides reliable line handling for vang, cunningham, trapeze retriever, leech line, and bunk adjustment systems while requiring virtually no maintenance.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe RF417 combines stainless steel cheeks with U.V.-stabilized Acetal sheaves for durable service in marine environments. Its double-sheave configuration supports efficient line routing, while the tube rivet design accepts fixing screws or shackles. The hollow rivet can also be used as a becket when additional purchase is needed, giving riggers more installation flexibility across a range of sailboat systems.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eUse the Ronstan Series 30 utility block on dinghies for vang, cunningham, and trapeze retriever systems. On larger yachts, it is suitable for applications such as leech line tackles and bunk adjusters. Its maintenance-free construction helps simplify ongoing equipment care, making it a practical choice for marine hardware installations where dependable, compact line control is required.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Lightweight durable construction\u003c\/strong\u003e – Provides practical marine hardware performance without unnecessary bulk.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Double utility block design\u003c\/strong\u003e – Supports efficient routing for a variety of sailboat control lines.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: U.V.-stabilized Acetal sheaves\u003c\/strong\u003e – Designed for durable use in boating applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Grade 316 stainless steel cheeks\u003c\/strong\u003e – Provides corrosion-resistant marine construction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Hollow tube rivet\u003c\/strong\u003e – Accepts fixing screws or shackles and can serve as a becket for extra purchase.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Maintenance-free construction\u003c\/strong\u003e – Helps reduce routine upkeep requirements.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e RF417\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 30\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Double utility block with tube rivet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave material:\u003c\/strong\u003e U.V.-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek material:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecommended applications:\u003c\/strong\u003e Dinghy vang, cunningham, and trapeze retriever systems; larger-yacht leech line tackles and bunk adjusters\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF417 Series 30 Double Utility Block for versatile, low-maintenance line control in demanding sailing and rigging applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO META DESCRIPTION:\u003c\/strong\u003e Shop the Ronstan RF417 Series 30 double utility block with tube rivet, Acetal sheaves, and stainless steel cheeks for marine rigging.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLightweight durable construction – Provides practical marine hardware performance without unnecessary bulk.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eDouble utility block design – Supports efficient routing for a variety of sailboat control lines.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eU.V.-stabilized Acetal sheaves – Designed for durable use in boating applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eGrade 316 stainless steel cheeks – Provides corrosion-resistant marine construction.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eHollow tube rivet – Accepts fixing screws or shackles and can serve as a becket for extra purchase.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eMaintenance-free construction – Helps reduce routine upkeep requirements.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881642422361,"sku":"72299","price":38.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/72299XL.jpg?v=1789190708"},{"product_id":"ronstan-rf681-series-30-utility-block-single-becket-with-loop-head","title":"Ronstan RF681 Series 30 Utility Block, Single Becket with Loop Head","description":"\u003cp\u003e\u003cstrong\u003eSeries 30 Utility Block - Single, Becket, Loop Head\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eLightweight durable construction\u003c\/li\u003e\n\u003cli\u003eEconomical\u003c\/li\u003e\n\u003cli\u003eMaintenance free\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eProduct Information:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eStainless steel cheeks and Acetal sheaves ensure a long service life with virtually no maintenance. Hollow rivets in the block heads can be fitted with shackles, which can also be used to add a becket for extra purchase.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eVang, cunningham and trapeze retriever systems on dinghies\u003c\/li\u003e\n\u003cli\u003eLeech line tackles, bunk adjusters etc on larger yachts\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU.V. stabilized Acetal sheaves\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF681 Series 30 Utility Block\u003c\/strong\u003e is a compact, lightweight block designed for sailors and boat owners who need dependable line handling in dinghy and yacht control systems. Its single sheave, becket-compatible loop head, and durable construction make it a practical choice for vang, cunningham, trapeze retriever, leech line, and bunk adjustment applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eBuilt with Grade 316 stainless steel cheeks and UV-stabilized Acetal sheaves, this Ronstan utility block is designed for durability in marine environments. The stainless steel cheeks provide a robust structure, while the Acetal sheave material supports reliable line movement and long service life. The block’s lightweight construction helps support efficient rigging without adding unnecessary weight.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe hollow rivets in the block head can be fitted with shackles, and the shackle arrangement can also be used to add a becket for extra purchase. This flexible design allows the RF681 to adapt to different rigging setups while maintaining a compact footprint. Use it on dinghies for vang, cunningham, and trapeze retriever systems, or on larger yachts for leech line tackles, bunk adjusters, and similar applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Lightweight, durable construction for practical marine rigging applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Single utility block with a loop head and becket-compatible design.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Stainless steel cheeks and UV-stabilized Acetal sheave for long service life.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Maintenance-free design helps simplify ongoing use.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Suitable for dinghy control systems and selected yacht adjustment tackles.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e RF681\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Series 30 utility block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e Single, becket, loop head\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave Material:\u003c\/strong\u003e UV-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek Material:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.96 lb\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplications:\u003c\/strong\u003e Vang, cunningham, trapeze retriever systems, leech line tackles, and bunk adjusters\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF681 Series 30 Utility Block for a durable, adaptable solution to everyday sailboat rigging needs.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Ronstan RF681 Series 30 utility block with single becket and loop head, stainless steel cheeks, and UV-stabilized Acetal sheave for marine rigging.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLightweight, durable construction for practical marine rigging applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSingle utility block with a loop head and becket-compatible design.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eStainless steel cheeks and UV-stabilized Acetal sheave for long service life.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eMaintenance-free design helps simplify ongoing use.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSuitable for dinghy control systems and selected yacht adjustment tackles.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881642881113,"sku":"72293","price":34.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/72293XL.jpg?v=1789190766"},{"product_id":"barton-marine-size-0-20mm-plain-bearing-pulley-block-with-single-swivel-becket-n00191","title":"Barton Marine Size 0 20mm Plain Bearing Pulley Block with Single Swivel \u0026 Becket, N00191","description":"\u003cp id=\"isPasted\"\u003e\u003cstrong\u003eSize 0 20mm Plain Bearing Pulley Block Single Swivel  Becket\u003c\/strong\u003e\u003c\/p\u003e\u003cp id=\"isPasted\"\u003eThe Barton Size 0 Plain bearing block has 20mm (3\/4) sheaves and is also available in ball bearing sheaves. They are designed for high strength and performance but lightweight with the range starting at only 13gms (0.5oz).\u003c\/p\u003e\u003cp\u003eSuitable for up to 6mm (1\/4) rope Ideal for use on dinghies, day boats smaller craft or lead blocks, flag pennants, etc. on larger yachts.\u003c\/p\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eBarton Marine Size 0 20mm Plain Bearing Pulley Block with Single Swivel \u0026amp; Becket\u003c\/strong\u003e is a lightweight, high-strength block designed for dinghies, day boats, smaller craft, and select lead-block or flag-pennant applications on larger yachts. Part number N00191 features a 20mm plain bearing sheave and is designed for use with rope up to 6mm (1\/4 inch), providing a practical solution for compact marine control and routing applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe Barton Marine Size 0 range is designed to deliver strength and performance while keeping weight low. This single-sheave pulley block combines a swivel attachment with a becket, making it suitable for applications where compact hardware and flexible positioning are important. Its plain bearing configuration offers a straightforward option for marine setups that do not require the ball-bearing version of the block.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eUse this pulley block on dinghies, day boats, and smaller sailing craft, or as a lead block for selected systems on larger yachts. It can also be used with flag pennants and other appropriate marine applications requiring support for rope up to 6mm. The compact Size 0 format makes it suitable where lightweight, space-conscious hardware is preferred. As part of the Barton Marine block range, it is built for practical use in sailing and boating equipment configurations.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKEY FEATURES:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eFeature: 20mm plain bearing sheave\u003c\/strong\u003e — Provides a compact pulley block configuration for suitable marine applications.\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eFeature: Single swivel and becket\u003c\/strong\u003e — Supports flexible attachment and routing in compatible sailing and boating setups.\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eFeature: Designed for rope up to 6mm (1\/4 inch)\u003c\/strong\u003e — Matches the rope capacity specified for this Size 0 block.\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eFeature: Lightweight, high-strength design\u003c\/strong\u003e — Barton Marine designed the range for strength and performance while maintaining low weight.\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eFeature: Versatile marine use\u003c\/strong\u003e — Suitable for dinghies, day boats, smaller craft, lead blocks, and flag pennants on larger yachts.\u003c\/li\u003e\n\u003cbr\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003ePRODUCT DETAILS:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Barton Marine\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e N00191\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Size 0 pulley block\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eSheave type:\u003c\/strong\u003e Plain bearing\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eSheave size:\u003c\/strong\u003e 20mm (3\/4 inch)\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e Single swivel with becket\u003c\/li\u003e\n\u003cbr\u003e\u003cli\u003e\n\u003cstrong\u003eMaximum compatible rope size:\u003c\/strong\u003e 6mm (1\/4 inch)\u003c\/li\u003e\n\u003cbr\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Barton Marine N00191 when you need a compact Size 0 plain bearing pulley block for an appropriate sailing or boating application.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO META DESCRIPTION:\u003c\/strong\u003e Shop the Barton Marine N00191 Size 0 20mm plain bearing pulley block with swivel and becket for rope up to 6mm on boats and yachts.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003e20mm plain bearing sheave for compact marine pulley applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSingle swivel and becket configuration for flexible attachment and rope routing.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eDesigned for rope up to 6mm (1\/4 inch).\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLightweight, high-strength design focused on practical marine performance.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSuitable for dinghies, day boats, smaller craft, lead blocks, and flag pennants on larger yachts.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Barton Marine","offers":[{"title":"Default Title","offer_id":44881651794009,"sku":"106547","price":33.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/106547XL.jpg?v=1789191586"},{"product_id":"ronstan-rf15202-series-15-double-ball-bearing-utility-block-with-loop-head","title":"Ronstan RF15202 Series 15 Double Ball Bearing Utility Block with Loop Head","description":"\u003cp\u003e\u003cstrong\u003eSeries 15 Ball Bearing Utility Block - Double, Loop Head\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSmallest and lightest ball bearing block available\u003c\/li\u003e\n\u003cli\u003ePrecision molded acetal sheave running on stainless steel ball bearings provide high performance  low friction\u003c\/li\u003e\n\u003cli\u003eSingle loop head blocks include an O-ring to separate running line from head lashing or fixing\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eDinghy control lines\u003c\/li\u003e\n\u003cli\u003eVangs, cunninghams and tweakers\u003c\/li\u003e\n\u003cli\u003eShock cord tensioning systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBB sheaves: UV stabilized acetal\u003c\/li\u003e\n\u003cli\u003eBall bearings: Stainless steel\u003c\/li\u003e\n\u003cli\u003eCheeks: Grade 316 stainless steel\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF15202 Series 15 Ball Bearing Utility Block\u003c\/strong\u003e is a compact double block designed for sailors, riggers, and dinghy owners who need smooth, low-friction control-line performance in a lightweight format. Its loop head supports practical installation for a range of small-boat rigging applications, including dinghy control lines, vangs, cunninghams, tweakers, and shock cord tensioning systems.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe precision-molded acetal sheaves run on stainless steel ball bearings to support high-performance, low-friction operation. This construction helps the block handle the repeated movement associated with control lines and tensioning systems while maintaining a compact profile. The single loop head design includes an O-ring that separates the running line from the head lashing or fixing, helping organize the connection point during installation and use.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Double ball bearing utility block.\u003c\/strong\u003e Provides two sheaves in a compact format for small-boat control-line systems.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Precision-molded acetal sheaves.\u003c\/strong\u003e The UV-stabilized acetal construction supports smooth, low-friction line movement.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Stainless steel ball bearings.\u003c\/strong\u003e Designed to provide high-performance operation within the Series 15 block format.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Loop head with O-ring.\u003c\/strong\u003e Separates the running line from head lashing or fixing for a practical rigging connection.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Compact and lightweight design.\u003c\/strong\u003e Well suited to dinghy rigging and other applications where space and weight are important considerations.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e RF15202\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 15 double ball bearing utility block with loop head\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave material:\u003c\/strong\u003e UV-stabilized acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearing material:\u003c\/strong\u003e Stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek material:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplications:\u003c\/strong\u003e Dinghy control lines, vangs, cunninghams, tweakers, and shock cord tensioning systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF15202 for a dependable, space-conscious solution for small-boat control lines and related sailing rigging applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Shop the Ronstan RF15202 double ball bearing utility block with loop head for smooth, low-friction performance in dinghy and small-boat rigging.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eDouble ball bearing utility block for compact small-boat control-line systems.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003ePrecision-molded UV-stabilized acetal sheaves support smooth, low-friction operation.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eStainless steel ball bearings provide high-performance block operation.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLoop head includes an O-ring to separate the running line from head lashing or fixing.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eGrade 316 stainless steel cheeks provide the specified block construction.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSuitable for dinghy control lines, vangs, cunninghams, tweakers, and shock cord tensioning systems.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881665785945,"sku":"71027","price":40.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/71027XL.jpg?v=1789193140"},{"product_id":"ronstan-rf15174-series-15-ball-bearing-utility-block-pivoting-lead-block","title":"Ronstan RF15174 Series 15 Ball Bearing Utility Block – Pivoting Lead Block","description":"\u003cp\u003e\u003cstrong\u003eSeries 15 Ball Bearing Utility Block - Pivoting Lead Block\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSmallest and lightest ball bearing block available\u003c\/li\u003e\n\u003cli\u003ePrecision molded acetal sheave running on stainless steel ball bearings provide high performance  low friction\u003c\/li\u003e\n\u003cli\u003eSingle loop head blocks include an O-ring to separate running line from head lashing or fixing\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eFeaturing a 4-point fastening for load distribution and low profile. Can be mounted without disassembly.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eDinghy control lines\u003c\/li\u003e\n\u003cli\u003eVangs, cunninghams and tweakers\u003c\/li\u003e\n\u003cli\u003eShock cord tensioning systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBB sheaves: UV stabilized acetal\u003c\/li\u003e\n\u003cli\u003eBall bearings: Stainless steel\u003c\/li\u003e\n\u003cli\u003eCheeks: Grade 316 stainless steel\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 15 Ball Bearing Utility Block - Pivoting Lead Block\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eDesigned for compact sailing control systems, the Ronstan RF15174 Series 15 Ball Bearing Utility Block provides smooth, low-friction line handling in a lightweight, low-profile design. This pivoting lead block is suited to dinghy control lines, vangs, cunningham systems, tweakers, and shock cord tensioning systems where dependable routing and efficient operation are important.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLightweight utility block:\u003c\/strong\u003e The Series 15 design is recognized as the smallest and lightest ball bearing block available, making it well suited to space-conscious control-line installations.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow-friction performance:\u003c\/strong\u003e A precision-molded, UV-stabilized acetal sheave runs on stainless steel ball bearings to support smooth line movement.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow-profile mounting:\u003c\/strong\u003e Four-point fastening helps distribute the load while maintaining a compact installation profile.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSimple installation:\u003c\/strong\u003e The block can be mounted without disassembly, helping streamline setup and replacement.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSingle loop head design:\u003c\/strong\u003e An O-ring separates the running line from the head lashing or fixing for organized line management.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e RF15174\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 15 ball bearing utility block with pivoting lead block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave material:\u003c\/strong\u003e UV-stabilized acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearing material:\u003c\/strong\u003e Stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek material:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecommended applications:\u003c\/strong\u003e Dinghy control lines, vangs, cunningham systems, tweakers, and shock cord tensioning systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF15174 for a compact, smoothly operating line-routing solution built around proven materials and practical installation features.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Ronstan RF15174 Series 15 ball bearing utility block with pivoting lead design, low-friction sheave, and compact mounting for sailing control lines.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLightweight Series 15 ball bearing utility block designed for compact control-line installations\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003ePrecision-molded UV-stabilized acetal sheave with stainless steel ball bearings for smooth, low-friction operation\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eFour-point fastening distributes load while maintaining a low-profile design\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eMounts without disassembly for streamlined installation\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSingle loop head includes an O-ring to separate the running line from the head lashing or fixing\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eConstructed with UV-stabilized acetal, stainless steel, and Grade 316 stainless steel components\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881666146393,"sku":"71025","price":53.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/71025XL.jpg?v=1789193203"},{"product_id":"ronstan-rf15101-series-15-ball-bearing-utility-block-single-block-with-loop-head","title":"Ronstan RF15101 Series 15 Ball Bearing Utility Block – Single Block with Loop Head","description":"\u003cp\u003e\u003cstrong\u003eSeries 15 Ball Bearing Utility Block - Single Block, Loop Head\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSmallest and lightest ball bearing block available\u003c\/li\u003e\n\u003cli\u003ePrecision molded acetal sheave running on stainless steel ball bearings provide high performance  low friction\u003c\/li\u003e\n\u003cli\u003eSingle loop head blocks include an O-ring to separate running line from head lashing or fixing\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eDinghy control lines\u003c\/li\u003e\n\u003cli\u003eVangs, cunninghams and tweakers\u003c\/li\u003e\n\u003cli\u003eShock cord tensioning systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBB sheaves: UV stabilized acetal\u003c\/li\u003e\n\u003cli\u003eBall bearings: Stainless steel\u003c\/li\u003e\n\u003cli\u003eCheeks: Grade 316 stainless steel\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF15101 Series 15 Ball Bearing Utility Block\u003c\/strong\u003e is a compact, lightweight single block designed for dinghy control lines, sailboat adjustment systems, and shock cord tensioning applications. Its loop head configuration provides a practical attachment point, while the precision-molded sheave and stainless steel ball bearings support smooth, low-friction line movement in compact rigging setups.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eBuilt for applications where efficient line handling and minimal weight are important, this Ronstan ball bearing block is suited to vangs, cunninghams, tweakers, and other dinghy control systems. The single loop head includes an O-ring that helps separate the running line from the head lashing or fixing, providing a more organized installation. Its compact Series 15 format is well suited to smaller control lines and space-conscious rigging configurations.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKEY FEATURES:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Compact, lightweight design:\u003c\/strong\u003e The Series 15 utility block is Ronstan’s smallest and lightest ball bearing block, making it suitable for weight-conscious control-line systems.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Precision-molded acetal sheave:\u003c\/strong\u003e The UV-stabilized acetal sheave is designed to support high-performance, low-friction operation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Stainless steel ball bearings:\u003c\/strong\u003e Ball bearings help the sheave run smoothly for responsive line adjustment.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Single loop head with O-ring:\u003c\/strong\u003e The O-ring separates the running line from head lashing or fixing during installation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Versatile rigging applications:\u003c\/strong\u003e Suitable for dinghy control lines, vangs, cunninghams, tweakers, and shock cord tensioning systems.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003ePRODUCT DETAILS:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e RF15101\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 15 ball bearing utility block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e Single block with loop head\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave material:\u003c\/strong\u003e UV-stabilized acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBall bearing material:\u003c\/strong\u003e Stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek material:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF15101 Series 15 Ball Bearing Utility Block for compact, low-friction control-line performance and dependable loop-head installation in dinghy and sailing rigging systems.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO META DESCRIPTION:\u003c\/strong\u003e Ronstan RF15101 Series 15 ball bearing utility block with loop head delivers compact, low-friction control for dinghy lines, vangs, and tweakers.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eCompact, lightweight Series 15 design for weight-conscious dinghy and sailing control-line systems.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003ePrecision-molded UV-stabilized acetal sheave supports high-performance, low-friction operation.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eStainless steel ball bearings help the sheave run smoothly for responsive line adjustment.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSingle loop head includes an O-ring to separate the running line from head lashing or fixing.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSuitable for dinghy control lines, vangs, cunninghams, tweakers, and shock cord tensioning systems.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881666441305,"sku":"71020","price":28.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/71020XL.jpg?v=1789193232"},{"product_id":"ronstan-rf20141-series-20-single-ball-bearing-block-with-stand-up-loop-top","title":"Ronstan RF20141 Series 20 Single Ball Bearing Block with Stand-Up Loop Top","description":"\u003cp\u003e\u003cstrong\u003eSeries 20 Ball Bearing Block- Single, Stand-Up Loop Top\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eLow friction\u003c\/li\u003e\n\u003cli\u003eHigh static and dynamic load capacity\u003c\/li\u003e\n\u003cli\u003eLightweight\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003ePrecision molded Acetal sheaves running on stainless steel or Torlon ball bearings provide high performance  low friction.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eDinghy control lines\u003c\/li\u003e\n\u003cli\u003eDinghy vangs\u003c\/li\u003e\n\u003cli\u003eCunninghams\u003c\/li\u003e\n\u003cli\u003eTraveler controls\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eStainless steel ball bearings\u003c\/li\u003e\n\u003cli\u003eUV stabilized Acetal sheave\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel load strap and head fitting\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF20141 Series 20 Single Ball Bearing Block with Stand-Up Loop Top\u003c\/strong\u003e is a lightweight, low-friction sailboat block designed for dinghy control lines, dinghy vangs, Cunninghams, and traveler controls. Its compact single-sheave configuration helps provide smooth line handling while supporting both static and dynamic loads in a range of small-craft sailing applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe precision-molded Acetal sheave operates on stainless steel ball bearings to support high-performance, low-friction movement. This construction is suited to control-line systems where responsive handling and reliable load support are important. The stand-up loop top provides a practical attachment arrangement for appropriate sailing hardware and rigging layouts.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eRonstan builds the Series 20 block with materials selected for marine use, including a UV-stabilized Acetal sheave, Grade 316 stainless steel load strap and head fitting, and impact- and UV-resistant, fiber-reinforced Nylon cheeks. These materials help define the block’s lightweight construction while supporting its intended use on dinghies and other small sailboats. The RF20141 is a focused solution for sailors and riggers looking to replace or configure control-line hardware with a Ronstan Series 20 ball bearing block.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Low-friction operation\u003c\/strong\u003e — Precision-molded Acetal sheave and ball-bearing construction support smooth control-line movement.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Load capacity\u003c\/strong\u003e — Designed for high static and dynamic load capacity in suitable sailing control applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Lightweight construction\u003c\/strong\u003e — Helps provide practical hardware for dinghy and small-craft rigging systems.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Stand-up loop top\u003c\/strong\u003e — Provides a single-block configuration for compatible attachment and control-line layouts.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Marine-oriented materials\u003c\/strong\u003e — Includes stainless steel, UV-stabilized Acetal, and impact- and UV-resistant fiber-reinforced Nylon components.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e RF20141\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 20 single ball bearing block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTop style:\u003c\/strong\u003e Stand-up loop top\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave:\u003c\/strong\u003e Precision-molded UV-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearings:\u003c\/strong\u003e Stainless steel ball bearings\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoad strap and head fitting:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheeks:\u003c\/strong\u003e Impact- and UV-resistant, fiber-reinforced Nylon\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplications:\u003c\/strong\u003e Dinghy control lines, dinghy vangs, Cunninghams, and traveler controls\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF20141 Series 20 block for purpose-built, low-friction control-line hardware in dinghy and small-craft sailing applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Shop the Ronstan RF20141 Series 20 single ball bearing block with stand-up loop top for low-friction dinghy and small-craft control lines.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLow-friction operation — Precision-molded Acetal sheave and ball-bearing construction support smooth control-line movement.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eHigh static and dynamic load capacity — Designed for suitable dinghy and small-craft sailing control applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLightweight construction — Practical for dinghy control lines, vangs, Cunninghams, and traveler controls.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eStand-up loop top — Single-block configuration for compatible sailing hardware and rigging layouts.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eMarine-oriented materials — UV-stabilized Acetal, Grade 316 stainless steel, and fiber-reinforced Nylon components.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881668669529,"sku":"70783","price":37.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70783XL.jpg?v=1789193467"},{"product_id":"ronstan-series-50-all-purpose-fiddle-block-with-becket-and-cleat-rf51530","title":"Ronstan Series 50 All Purpose Fiddle Block with Becket and Cleat RF51530","description":"\u003cp\u003e\u003cstrong\u003eSeries 50 All Purpose Block - Fiddle - Becket - Cleat\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance, long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating Acetal polymer sheave ensures low friction and extreme durability\u003c\/li\u003e\n\u003cli\u003eCaptive Lock universal head\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003cli\u003eSnap fit removable becket pin\u003c\/li\u003e\n\u003cli\u003eMulti-position cleat arm\u003c\/li\u003e\n\u003cli\u003eSpare Parts - RF51010 Replacement Becket Pin, RF150 Shackle\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.Captive Lock universal head can be fixed in either of two planes, or free to swivel as required. Quick adjusting cleat arms require no tools to adjust and fix securely in position. Becket pin is removable so line can be spliced prior to fitting and is \u003cstrong\u003ei\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eAppllications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet and halyard applications, vang and spinnaker control lines on boats to 10m (33ft)\u003c\/li\u003e\n\u003cli\u003eS60 - on boats up to 12m (40ft)\u003c\/li\u003e\n\u003cli\u003eIdeal for fine-tune mainsheet tackles, cunninghams, backstays and other control line purchase systems.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eGrade 316 stainless steel load strap\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003eThe Ronstan Series 50 All Purpose Fiddle Block with Becket and Cleat RF51530 is a versatile sailboat control-line block designed for cruising and racing applications. It provides a practical solution for mainsheets, halyards, vangs, spinnaker controls, and other purchase systems where dependable handling, high working loads, and easy adjustment are important.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eIts self-lubricating Acetal polymer sheave runs on polished stainless steel races to help reduce friction while supporting durability under both dynamic and high static loads. The Captive Lock universal head can be fixed in either of two planes or allowed to swivel as needed, giving sailors flexibility when routing lines and configuring onboard hardware. The multi-position cleat arm adjusts quickly without tools and secures firmly in place for convenient line control.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe removable becket pin allows line splicing before installation, while the slotted pin shackle helps reduce the chance of fouled lines. Built with a Grade 316 stainless steel load strap and impact- and UV-resistant, fiber-reinforced Nylon cheeks, this Ronstan Series 50 block is suited to mainsheet and halyard applications on boats up to 33 feet, as well as vang, spinnaker control, fine-tune mainsheet tackle, Cunningham, backstay, and other control-line systems. For larger boats up to 40 feet, Ronstan identifies the Series 60 as the appropriate option.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-load performance:\u003c\/strong\u003e Designed for applications requiring exceptionally high working loads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow-friction sheave:\u003c\/strong\u003e Self-lubricating Acetal polymer sheave runs on polished stainless steel races.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCaptive Lock universal head:\u003c\/strong\u003e Fixes in two planes or swivels as required for flexible installation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdjustable cleat arm:\u003c\/strong\u003e Multi-position arm adjusts without tools and locks securely in position.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLine-friendly hardware:\u003c\/strong\u003e Slotted pin shackle helps prevent fouled lines, and the removable becket pin supports pre-installation splicing.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 50 All Purpose\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e RF51530\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e Fiddle block with becket and cleat\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoad strap:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheeks:\u003c\/strong\u003e Impact- and UV-resistant, fiber-reinforced Nylon\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReplacement parts:\u003c\/strong\u003e RF51010 replacement becket pin and RF150 shackle\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntended use:\u003c\/strong\u003e Sailboat sheets, halyards, vangs, spinnaker controls, and control-line purchase systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF51530 Series 50 All Purpose Block for versatile, serviceable line control on cruising and racing sailboats.\u003c\/p\u003e\u003cbr\u003eSEO META DESCRIPTION:\u003cbr\u003eRonstan RF51530 Series 50 fiddle block with becket and cleat delivers versatile, low-friction line control for cruising and racing sailboats.\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eHigh-load performance: Designed for applications requiring exceptionally high working loads.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLow-friction sheave: Self-lubricating Acetal polymer sheave runs on polished stainless steel races.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCaptive Lock universal head: Fixes in two planes or swivels as required for flexible installation.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eAdjustable cleat arm: Multi-position arm adjusts without tools and locks securely in position.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLine-friendly hardware: Slotted pin shackle helps prevent fouled lines, and the removable becket pin supports pre-installation splicing.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881668800601,"sku":"70688","price":141.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70688XL.jpg?v=1789193492"},{"product_id":"ronstan-rf51510-series-50-all-purpose-fiddle-becket-block","title":"Ronstan RF51510 Series 50 All Purpose Fiddle Becket Block","description":"\u003cp\u003e\u003cstrong\u003eSeries 50 All Purpose Block - Fiddle - Becket\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance, long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating Acetal polymer sheave ensures low friction and extreme durability\u003c\/li\u003e\n\u003cli\u003eCaptive Lock universal head\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003cli\u003eSnap fit removable becket pin\u003c\/li\u003e\n\u003cli\u003eSpare Parts - RF51010 Replacement Becket Pin, RF150 Shackle\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.Captive Lock universal head can be fixed in either of two planes, or free to swivel as required. Becket pin is removable so line can be spliced prior to fitting and is ingeniously locked into position without the use of a clevis pin, split ring or tools\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet and halyard applications, vang and spinnaker control lines on boats to 10m (33ft)\u003c\/li\u003e\n\u003cli\u003eS60 - on boats up to 12m (40ft)\u003c\/li\u003e\n\u003cli\u003eIdeal for fine-tune mainsheet tackles, cunninghams, backstays and other control line purchase systems.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eGrade 316 stainless steel load strap\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF51510 Series 50 All Purpose Fiddle Becket Block\u003c\/strong\u003e delivers a versatile, durable solution for sailors who need dependable control of sheets, halyards, and purchase systems. Designed for cruising and racing applications, this fiddle becket block combines high working loads, low friction, and practical line-handling features for mainsheet systems, vang controls, spinnaker controls, cunningham tackles, backstays, and other onboard applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe self-lubricating Acetal polymer sheave runs on polished stainless steel races to support smooth operation with both dynamic and high static loads. Its construction is intended to provide low maintenance and a long service life, while the impact- and UV-resistant, fiber-reinforced Nylon cheeks add durability for demanding marine use. The Grade 316 stainless steel load strap provides a robust foundation for the block assembly.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe Captive Lock universal head can be fixed in either of two planes or left free to swivel as needed, giving sailors flexibility when configuring running rigging. A slotted pin shackle helps reduce the risk of fouled lines, while the snap-fit removable becket pin allows line splicing before installation. The becket pin locks into position without requiring a clevis pin, split ring, or tools. This Series 50 block is suited for mainsheet and halyard applications, vang and spinnaker control lines on boats up to 33 feet, and fine-tune control systems where an efficient fiddle becket arrangement is needed.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh working loads:\u003c\/strong\u003e Supports demanding dynamic and static marine line-handling applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSelf-lubricating Acetal sheave:\u003c\/strong\u003e Provides low-friction operation and durable performance on polished stainless steel races.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCaptive Lock universal head:\u003c\/strong\u003e Can be fixed in two planes or allowed to swivel according to the rigging setup.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemovable becket pin:\u003c\/strong\u003e Allows line splicing before installation and locks into place without tools.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSlotted pin shackle:\u003c\/strong\u003e Helps prevent lines from becoming fouled during use.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e RF51510\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 50 all purpose fiddle becket block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterials:\u003c\/strong\u003e Grade 316 stainless steel load strap; impact- and UV-resistant, fiber-reinforced Nylon cheeks; Acetal polymer sheave\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplications:\u003c\/strong\u003e Mainsheets, halyards, vang and spinnaker control lines, cunningham tackles, backstays, and other control line purchase systems\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecommended boat use:\u003c\/strong\u003e Applications on boats up to 33 feet; S60 applications are for boats up to 40 feet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReplacement parts:\u003c\/strong\u003e RF51010 replacement becket pin and RF150 shackle\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF51510 Series 50 All Purpose Fiddle Becket Block for a practical, serviceable, and versatile addition to your boat’s running rigging.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Ronstan RF51510 Series 50 fiddle becket block delivers low-friction, durable control for mainsheets, halyards, vangs, and marine rigging systems.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eHigh working loads: Supports demanding dynamic and static marine line-handling applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSelf-lubricating Acetal polymer sheave: Delivers low-friction operation and durable performance on polished stainless steel races.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCaptive Lock universal head: Can be fixed in two planes or left free to swivel for flexible rigging configurations.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSlotted pin shackle: Helps reduce the chance of fouled lines during use.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSnap-fit removable becket pin: Allows line splicing before installation and locks into position without tools.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eDurable marine construction: Combines a Grade 316 stainless steel load strap with impact- and UV-resistant, fiber-reinforced Nylon cheeks.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881668898905,"sku":"70687","price":86.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70687XL.jpg?v=1789193512"},{"product_id":"ronstan-rf51300-series-50-all-purpose-triple-block-for-sailboat-sheets-halyards-and-control-lines","title":"Ronstan RF51300 Series 50 All Purpose Triple Block for Sailboat Sheets, Halyards and Control Lines","description":"\u003cp\u003e\u003cstrong\u003eSeries 50 All Purpose\u003c\/strong\u003e\u003cstrong\u003eBlock - Triple\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance, long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating Acetal polymer sheave ensures low friction and extreme durability\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003cli\u003eLockable swiveling head post\u003c\/li\u003e\n\u003cli\u003eSnap fit removable becket pin\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.Head can be locked at 0 or 90 by engaging the grub screw in either the 0 or 90 degree position.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet and halyard applications, vang and spinnaker control lines on boats to 10m (33ft)\u003c\/li\u003e\n\u003cli\u003eS60 - on boats up to 12m (40ft)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eGrade 316 stainless steel load strap\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003eThe Ronstan RF51300 Series 50 All Purpose Triple Block is a durable, versatile sailing block designed for cruising and racing applications. Its triple-sheave configuration supports mainsheets, halyards, vangs and spinnaker control lines on boats up to 33 feet, while the Series 50 design also suits demanding dynamic and high static load conditions. With low friction, durable construction and flexible installation features, this Ronstan triple block provides a practical solution for a wide range of sailboat control systems.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eSelf-lubricating Acetal polymer sheaves run on polished stainless steel races to help reduce friction and support a long service life with low maintenance. The impact- and UV-resistant fiber-reinforced Nylon cheeks are paired with a Grade 316 stainless steel load strap for dependable construction. A slotted pin shackle helps prevent fouled lines, while the lockable swiveling head post can be secured at 0 or 90 degrees by engaging the grub screw in the selected position.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe snap-fit removable becket pin makes servicing and line arrangement more convenient. This all purpose block is intended for mainsheet and halyard applications, as well as vang and spinnaker control lines. Series 50 blocks are suitable for boats up to 33 feet, and the manufacturer also identifies S60 applications for boats up to 40 feet. Whether outfitting a cruising sailboat or preparing a racing control system, the Ronstan RF51300 delivers versatile performance in a compact, serviceable design.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFeature: Triple-sheave all purpose block for sheets, halyards and control lines\u003c\/li\u003e\n\u003cli\u003eFeature: Self-lubricating Acetal polymer sheaves help reduce friction and support durability\u003c\/li\u003e\n\u003cli\u003eFeature: Polished stainless steel races support dynamic and high static load applications\u003c\/li\u003e\n\u003cli\u003eFeature: Slotted pin shackle helps eliminate fouled lines\u003c\/li\u003e\n\u003cli\u003eFeature: Lockable swiveling head post secures at 0 or 90 degrees\u003c\/li\u003e\n\u003cli\u003eFeature: Snap-fit removable becket pin simplifies line arrangement and service\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBrand: Ronstan\u003c\/li\u003e\n\u003cli\u003eModel: RF51300\u003c\/li\u003e\n\u003cli\u003eProduct type: Series 50 All Purpose Triple Block\u003c\/li\u003e\n\u003cli\u003eLoad strap: Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003eCheeks: Impact- and UV-resistant fiber-reinforced Nylon\u003c\/li\u003e\n\u003cli\u003eSheaves: Self-lubricating Acetal polymer\u003c\/li\u003e\n\u003cli\u003eIntended use: Mainsheet, halyard, vang and spinnaker control line applications\u003c\/li\u003e\n\u003cli\u003eRecommended boat size: Up to 33 feet for Series 50 applications\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF51300 Series 50 Triple Block for a reliable, versatile solution to common sailboat rigging and control-line needs.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e\u003cbr\u003eShop the Ronstan RF51300 Series 50 Triple Block for sailboat sheets, halyards and control lines, with durable sheaves and a lockable swivel head.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eTriple-sheave all purpose block for sheets, halyards and control lines\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSelf-lubricating Acetal polymer sheaves help reduce friction and support durability\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003ePolished stainless steel races support dynamic and high static load applications\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSlotted pin shackle helps eliminate fouled lines\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLockable swiveling head post secures at 0 or 90 degrees\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSnap-fit removable becket pin simplifies line arrangement and service\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881668997209,"sku":"70685","price":118.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70685XL.jpg?v=1789193533"},{"product_id":"ronstan-series-50-all-purpose-double-block-rf51200-with-swivel-shackle","title":"Ronstan Series 50 All Purpose Double Block RF51200 with Swivel Shackle","description":"\u003cp\u003e\u003cstrong\u003eSeries 50 All Purpose Block - Double\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing. Swivel shackle head for full 360 degree rotation (non-locking).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance  long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating Acetal polymer sheave ensures low friction and extreme durability\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet and halyard applications, vang and spinnaker control lines on boats to (33ft). 10m\u003c\/li\u003e\n\u003cli\u003eS60 - on boats up to 40ft, (12m)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eGrade 316 stainless steel load strap\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eSpecifications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSheave Diameter: (inch) 2\" \/ (mm) 50\u003c\/li\u003e\n\u003cli\u003eMax Rope Diameter: (inch) 1\/2\" \/ (mm) 12\u003c\/li\u003e\n\u003cli\u003ePin Diameter: (inch) 1\/4\" \/ (mm) 6\u003c\/li\u003e\n\u003cli\u003eMaximum Working Load: (lb) 2200 \/ (kg) 1000\u003c\/li\u003e\n\u003cli\u003eBreaking Load: (lb) 4410 \/ (kg) 2000\u003c\/li\u003e\n\u003cli\u003eWeight: (oz) 9.0 \/ (g) 255\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 50 All Purpose Double Block RF51200\u003c\/strong\u003e provides a dependable solution for cruising and racing sailors who need efficient control of sheets, halyards, vang lines, and spinnaker control lines. Designed for dynamic and high static loads, this double block combines a self-lubricating Acetal polymer sheave with durable stainless steel and reinforced Nylon components for smooth operation, reduced maintenance, and long service life.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe swivel shackle head rotates 360 degrees to help align the block with changing line directions during sailing. Its non-locking design supports versatile rigging, while the slotted pin shackle helps eliminate fouled lines. The self-lubricating sheave is engineered for low friction and durability, making this Ronstan sailing block a practical choice for demanding onboard applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eHigh working load capacity: Supports demanding sheet, halyard, and control line applications.\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating Acetal polymer sheave: Helps provide low friction and durable performance.\u003c\/li\u003e\n\u003cli\u003e360-degree swivel shackle head: Allows full rotation for flexible line alignment.\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle: Helps prevent fouled lines during use.\u003c\/li\u003e\n\u003cli\u003eDurable construction: Combines a Grade 316 stainless steel load strap with impact- and UV-resistant, fiber-reinforced Nylon cheeks.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBrand: Ronstan\u003c\/li\u003e\n\u003cli\u003eSeries: 50\u003c\/li\u003e\n\u003cli\u003eProduct type: All purpose double block\u003c\/li\u003e\n\u003cli\u003ePart number: RF51200\u003c\/li\u003e\n\u003cli\u003eSheave diameter: 2 inches\u003c\/li\u003e\n\u003cli\u003eMaximum rope diameter: 1\/2 inch\u003c\/li\u003e\n\u003cli\u003ePin diameter: 1\/4 inch\u003c\/li\u003e\n\u003cli\u003eMaximum working load: 2,200 pounds\u003c\/li\u003e\n\u003cli\u003eBreaking load: 4,410 pounds\u003c\/li\u003e\n\u003cli\u003eHead style: Non-locking swivel shackle\u003c\/li\u003e\n\u003cli\u003eIntended applications: Mainsheets, halyards, vang lines, and spinnaker control lines\u003c\/li\u003e\n\u003cli\u003eRecommended boat use: Boats up to 33 feet for listed applications; S60 applications on boats up to 40 feet\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan Series 50 All Purpose Double Block RF51200 for reliable line handling and versatile performance aboard cruising and racing sailboats.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Ronstan Series 50 RF51200 double block with swivel shackle, low-friction Acetal sheave, and 2,200-pound working load for sailboats.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eHigh working load capacity: Supports demanding sheet, halyard, and control line applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSelf-lubricating Acetal polymer sheave: Helps provide low friction and durable performance.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003e360-degree swivel shackle head: Allows full rotation for flexible line alignment.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSlotted pin shackle: Helps prevent fouled lines during use.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eDurable construction: Combines a Grade 316 stainless steel load strap with impact- and UV-resistant, fiber-reinforced Nylon cheeks.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881669357657,"sku":"70683","price":88.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70683XL.jpg?v=1789193562"},{"product_id":"ronstan-series-50-all-purpose-single-stand-up-block-rf51140","title":"Ronstan Series 50 All Purpose Single Stand-Up Block RF51140","description":"\u003cp\u003e\u003cstrong\u003eSeries 50 All Purpose Block - Single Stand Up\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance, long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating Acetal polymer sheave ensures low friction and extreme durability\u003c\/li\u003e\n\u003cli\u003eCaptive Lock universal head\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003cli\u003eMount with 2 x 5mm (3\/6\") fasteners (not supplied)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.Captive Lock universal head can be fixed in either of two planes, or free to swivel as required. Quick adjusting cleat arms require no tools to adjust and fix securely in position. Becket pin is removable so line can be spliced prior to fitting.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet and halyard applications, vang and spinnaker control lines on boats to 10m (33ft)\u003c\/li\u003e\n\u003cli\u003eS60 - on boats up to 12m (40ft)\u003c\/li\u003e\n\u003cli\u003eTypically used in direct 4:1 purchase systems such as mainsheets and boom vangs\u003c\/li\u003e\n\u003cli\u003eOn larger boats they are used for fine-tune mainsheet tackles, outhauls, cunninghams, checkstays, genoa lead pullers and traveller controls.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eGrade 316 stainless steel load strap\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 50 All Purpose Single Stand-Up Block RF51140\u003c\/strong\u003e is a versatile sailing hardware solution for cruising and racing applications. Designed for mainsheets, halyards, vangs, spinnaker control lines, and other deck hardware systems, this single stand-up block combines high working loads, low friction, and durable construction for dependable line handling on boats up to 33 feet.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe self-lubricating Acetal polymer sheave runs on polished stainless steel races to support smooth operation under both dynamic and high static loads. Its construction is suited to demanding sheet, halyard, and control-line applications, while the impact- and UV-resistant fiber-reinforced Nylon cheeks help support a long service life with minimal maintenance. The removable becket pin also allows line splicing before installation.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Self-lubricating Acetal polymer sheave delivers low friction and high durability.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Polished stainless steel races support smooth performance with dynamic and static loads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Captive Lock universal head can be fixed in either of two planes or allowed to swivel as needed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Slotted pin shackle helps reduce the chance of fouled lines.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Quick-adjusting cleat arms require no tools and secure firmly in position.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Removable becket pin allows line splicing before fitting.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e 50 All Purpose\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e RF51140\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBlock Type:\u003c\/strong\u003e Single stand-up block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoad Strap:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheeks:\u003c\/strong\u003e Impact- and UV-resistant fiber-reinforced Nylon\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplications:\u003c\/strong\u003e Mainsheets, halyards, boom vangs, spinnaker control lines, outhauls, cunninghams, checkstays, genoa lead pullers, and traveler controls\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecommended Boat Size:\u003c\/strong\u003e Boats up to 33 feet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting:\u003c\/strong\u003e Requires fasteners, which are not supplied\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan Series 50 All Purpose Single Stand-Up Block RF51140 for a durable, adaptable addition to your sailing control-line system.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO META DESCRIPTION:\u003c\/strong\u003e\u003cbr\u003eShop the Ronstan Series 50 All Purpose Single Stand-Up Block RF51140 for durable sheet, halyard, and control-line handling on boats up to 33 feet.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eSelf-lubricating Acetal polymer sheave delivers low friction and high durability.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003ePolished stainless steel races support smooth performance with dynamic and static loads.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCaptive Lock universal head can be fixed in either of two planes or allowed to swivel as needed.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSlotted pin shackle helps reduce the chance of fouled lines.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eQuick-adjusting cleat arms require no tools and secure firmly in position.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eRemovable becket pin allows line splicing before fitting.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881669455961,"sku":"70680","price":63.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70680XL.jpg?v=1789193593"},{"product_id":"ronstan-rf45130-series-40-ball-bearing-orbit-block-single-becket-with-cleat-and-swivel-head","title":"Ronstan RF45130 Series 40 Ball Bearing Orbit Block, Single Becket with Cleat and Swivel Head","description":"\u003cp\u003e\u003cstrong\u003eSeries 40 Ball Bearing Orbit Block - Single - Becket - Cleat - Swivel Head\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eUltra Lightweight\u003c\/li\u003e\n\u003cli\u003eLow friction 2-stage Orbital ball bearing system\u003c\/li\u003e\n\u003cli\u003eHighest working load in its class\u003c\/li\u003e\n\u003cli\u003eLow profile and compact\u003c\/li\u003e\n\u003cli\u003eHigh performance cleating\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eLightweight\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eKilogram for kilogram of working load, BB and RT Orbit Blocks are the worlds lightest. The unique orbital design allows the bearing to only be in the active areas of the floating sheave. This minimizes the mass of the inactive return race and hub.\u003c\/p\u003e\u003cp\u003eWeight and bulk are further reduced in the different block configurations. The ball bearing single and becket block has a through-sheave becket arrangement. The result The lowest weight possible.\u003c\/p\u003e\u003cp\u003eMulti-sheave blocks have only single intermediate cheeks and an ultra-light and efficient head arrangement. This gives a 30% weight saving advantage over the nearest competitor. Other brands just link together their single blocks. This results in unnecessary double cheeks between each sheave, held together by a heavy steel channel across the top of the block.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHighest Working Load In It's Class\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe orbital ball-bearing arrangement gives the largest possible bearing race diameter. This maximizes load performance. The proven Ronstan 2-stage bearing system features high compression grade acetal ball bearings and a secondary full-contact bearing. This gives minimum friction across the full working load range.\u003c\/p\u003e\u003cp\u003eThe floating sheave and bearing system is supported by a fiber-reinforced load frame. The design was computer modeled to be stress optimized.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet systems on spinnaker sheet on dinghies to 5m (16ft)\u003c\/li\u003e\n\u003cli\u003eSpinnaker sheets on dinghies, sportsboats and small keel boats to 5m (16ft)\u003c\/li\u003e\n\u003cli\u003eHalyard, vang and backstay applications on boats to 8m (26ft)\u003c\/li\u003e\n\u003cli\u003eControl line applications on larger yachts\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBall Bearings - High compression strength carbon black Acetal.\u003c\/li\u003e\n\u003cli\u003eStage 2 Bearing - Glass fibre reinforced, MoS2 impregnated Nylon\u003c\/li\u003e\n\u003cli\u003eFrame\/Cheeks - Toughened, glass fibre reinforced Nylon\u003c\/li\u003e\n\u003cli\u003eSheave - Carbon fiber reinforced, PTFE impregnated Nylon\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 40 Ball Bearing Orbit Block RF45130\u003c\/strong\u003e is a lightweight, low-friction sailing block designed for dinghies, sportsboats, small keel boats, and larger yacht control-line systems. Its single-becket configuration with cleat and swivel head provides versatile line handling for mainsheet, spinnaker sheet, halyard, vang, and backstay applications while helping reduce weight and bulk aloft or within a control system.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe low-friction, two-stage orbital ball bearing system is engineered to support high working loads while allowing the bearing to remain concentrated in the active areas of the floating sheave. This orbital design reduces the mass of the inactive return race and hub. A through-sheave becket arrangement further contributes to the lightweight construction, while the low-profile, compact form\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003c\/p\u003e\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881669587033,"sku":"70624","price":109.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70624XL.jpg?v=1789193630"},{"product_id":"ronstan-series-40-ball-bearing-fiddle-block-with-becket-and-cleat-rf40530","title":"Ronstan Series 40 Ball Bearing Fiddle Block with Becket and Cleat, RF40530","description":"\u003cp\u003e\u003cstrong\u003eSeries 40 Ball Bearing Block - Fiddle - Becket - Cleat\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eLow friction Acetal or Torlon bearing system\u003c\/li\u003e\n\u003cli\u003eLightweight\u003c\/li\u003e\n\u003cli\u003eCheek cut-outs for easy bearing maintenance\u003c\/li\u003e\n\u003cli\u003eCaptive Lock universal head\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003cli\u003eSnap fit removable becket pin\u003c\/li\u003e\n\u003cli\u003eMulti-position cleat arm\u003c\/li\u003e\n\u003cli\u003eLow friction, 2-stage ball bearing system\u003c\/li\u003e\n\u003cli\u003eHigh static and dynamic load capacity\u003c\/li\u003e\n\u003cli\u003eLightweight\u003c\/li\u003e\n\u003cli\u003eCheek cut-outs for easy bearing maintenance\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSheaves running on Acetal or Torlon ball bearings provide high performance  low friction. The 2-stage ball bearing system provides consistent performance over the full load range.Captive Lock universal head can be fixed in either of two planes, or free to swivel as required. Quick adjusting cleat arms require no tools to adjust and fix securely in position. Becket pin is removable so line can be spliced prior to fitting and is i\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet\u003c\/li\u003e\n\u003cli\u003eHalyard\u003c\/li\u003e\n\u003cli\u003eVang\u003c\/li\u003e\n\u003cli\u003eSpinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft)\u003c\/li\u003e\n\u003cli\u003eTypically used in direct 4:1 purchase systems such as mainsheets and boom vangs\u003c\/li\u003e\n\u003cli\u003eOn larger boats they are used for fine-tune mainsheet tackles, outhauls, cunninghams, checkstays, genoa lead pullers and traveller controls.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eAcetal ball bearings\u003c\/li\u003e\n\u003cli\u003eUV stabilized Acetal sheave\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel load strap and head fitting\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 40 Ball Bearing Fiddle Block with Becket and Cleat\u003c\/strong\u003e is designed for sailors who need reliable, low-friction control for mainsheets, halyards, vangs, and other line-handling applications. Model RF40530 combines a fiddle block, becket, and adjustable cleat in one compact assembly, making it a practical choice for direct 4:1 purchase systems and control lines on off-the-beach catamarans, one-design classes, sportsboats, and larger boats.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eIts two-stage Acetal or Torlon ball bearing system helps provide smooth, consistent operation across the load range. The lightweight construction supports efficient rigging without adding unnecessary bulk, while the high static and dynamic load capacity suits a variety of sailing control applications. Cheek cut-outs provide access for easier bearing maintenance, helping simplify routine care and service.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe Captive Lock universal head can be fixed in either of two planes or left free to swivel as required. A multi-position cleat arm adjusts quickly without tools and secures firmly in position, allowing the cleat to be configured for convenient line handling. The slotted pin shackle helps reduce the chance of fouled lines, and the snap-fit removable becket pin allows the line to be prepared before fitting.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKEY FEATURES:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow-friction bearing system:\u003c\/strong\u003e Acetal or Torlon ball bearings support smooth, consistent performance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFiddle block with becket and cleat:\u003c\/strong\u003e Combines multiple rigging functions for mainsheets, vangs, halyards, and control lines.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCaptive Lock universal head:\u003c\/strong\u003e Can be fixed in two planes or allowed to swivel as required.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdjustable cleat arm:\u003c\/strong\u003e Multi-position design adjusts without tools and locks securely in place.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaintenance-friendly construction:\u003c\/strong\u003e Cheek cut-outs provide access to the bearing system.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLine-management features:\u003c\/strong\u003e Slotted pin shackle and removable becket pin help simplify setup and reduce fouling concerns.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003ePRODUCT DETAILS:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e Series 40\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e RF40530\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterials:\u003c\/strong\u003e Acetal ball bearings, UV-stabilized Acetal sheave, Grade 316 stainless steel load strap and head fitting, and impact- and UV-resistant fiber-reinforced nylon cheeks\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplications:\u003c\/strong\u003e Mainsheets, halyards, vangs, spinnaker control lines, outhauls, cunningham controls, checkstays, genoa lead pullers, and traveler controls\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTypical use:\u003c\/strong\u003e Direct 4:1 purchase systems, including mainsheets and boom vangs\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF40530 Series 40 fiddle block when dependable low-friction control and flexible cleat positioning are important to your sailing setup.\u003c\/p\u003e\u003cbr\u003eSEO META DESCRIPTION:\u003cbr\u003eRonstan Series 40 RF40530 fiddle block with becket and cleat offers low-friction ball bearings, adjustable cleat positioning, and versatile sailing control.\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLow-friction Acetal or Torlon two-stage ball bearing system\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eFiddle block with becket and multi-position cleat arm\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCaptive Lock universal head with fixed or swiveling configurations\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSlotted pin shackle helps reduce fouled lines\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSnap-fit removable becket pin\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCheek cut-outs for easier bearing maintenance\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881669718105,"sku":"70623","price":102.37,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70623XL.jpg?v=1789193653"},{"product_id":"ronstan-rf40300-series-40-triple-ball-bearing-block-with-swivel-head","title":"Ronstan RF40300 Series 40 Triple Ball Bearing Block with Swivel Head","description":"\u003cp\u003e\u003cstrong\u003eSeries 40 Ball Bearing Block - Triple - Swivel Head\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eLow friction Acetal or Torlon bearing system\u003c\/li\u003e\n\u003cli\u003eLightweight\u003c\/li\u003e\n\u003cli\u003eCheek cut-outs for easy bearing maintenance\u003c\/li\u003e\n\u003cli\u003eFeatures a swivel shackle head for full 360 rotation\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSheaves running on Acetal or Torlon ball bearings provide high performance  low friction. The 2-stage ball bearing system provides consistent performance over the full load range.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet\u003c\/li\u003e\n\u003cli\u003eHalyard\u003c\/li\u003e\n\u003cli\u003eVang\u003c\/li\u003e\n\u003cli\u003eSpinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eAcetal ball bearings\u003c\/li\u003e\n\u003cli\u003eUV stabilised Acetal sheave\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel load strap and head fitting\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 40 Triple Ball Bearing Block with Swivel Head\u003c\/strong\u003e is designed for sailors who need reliable, low-friction line control on off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet. Model RF40300 combines a lightweight construction with a two-stage ball bearing system to deliver consistent performance across the full load range, making it well suited for mainsheets, halyards, vangs, and spinnaker control lines.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow-friction bearing system:\u003c\/strong\u003e Acetal or Torlon ball bearings support smooth sheave operation and high-performance line handling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTriple sheave configuration:\u003c\/strong\u003e Provides multiple line-routing options for common sailboat control applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSwivel shackle head:\u003c\/strong\u003e Allows full 360-degree rotation to help the block align with changing line angles.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLightweight construction:\u003c\/strong\u003e Helps reduce unnecessary weight in sailing hardware installations.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek cut-outs:\u003c\/strong\u003e Provide access for easier bearing maintenance.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e RF40300\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 40 triple ball bearing block with swivel head\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplications:\u003c\/strong\u003e Mainsheet, halyard, vang, and spinnaker control lines\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecommended boat types:\u003c\/strong\u003e Off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearing material:\u003c\/strong\u003e Acetal ball bearings\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave material:\u003c\/strong\u003e UV-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoad strap and head fitting:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek material:\u003c\/strong\u003e Impact- and UV-resistant fiber-reinforced Nylon\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF40300 Series 40 triple block when your sailing setup calls for smooth, adaptable line control and durable marine-grade components in a lightweight design.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Shop the Ronstan RF40300 Series 40 triple ball bearing block with swivel head for smooth, low-friction control of mainsheets, halyards, vangs, and spinnaker lines.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLow-friction Acetal or Torlon ball bearing system supports smooth, consistent sheave performance.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eTriple sheave configuration suits mainsheet, halyard, vang, and spinnaker control lines.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSwivel shackle head provides full 360-degree rotation for flexible line alignment.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLightweight design helps reduce weight in sailing hardware installations.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCheek cut-outs make bearing maintenance easier.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eMarine-grade construction includes UV-stabilized Acetal, Grade 316 stainless steel, and fiber-reinforced Nylon components.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881670668377,"sku":"70618","price":100.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70618XL.jpg?v=1789193682"},{"product_id":"ronstan-rf40200-series-40-double-ball-bearing-block-with-swivel-head","title":"Ronstan RF40200 Series 40 Double Ball Bearing Block with Swivel Head","description":"\u003cp\u003e\u003cstrong\u003eSeries 40 Ball Bearing Block - Double - Swivel Head\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eLow friction Acetal or Torlon bearing system\u003c\/li\u003e\n\u003cli\u003eLightweight\u003c\/li\u003e\n\u003cli\u003eCheek cut-outs for easy bearing maintenance\u003c\/li\u003e\n\u003cli\u003eFeatures a swivel shackle head for full 360 rotation\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSheaves running on Acetal or Torlon ball bearings provide high performance  low friction. The 2-stage ball bearing system provides consistent performance over the full load range.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet\u003c\/li\u003e\n\u003cli\u003eHalyard\u003c\/li\u003e\n\u003cli\u003eVang\u003c\/li\u003e\n\u003cli\u003eSpinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft)\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 40 Double Ball Bearing Block with Swivel Head\u003c\/strong\u003e is designed for sailors who need smooth, dependable line handling on off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet. The RF40200 combines a low-friction bearing system with a swivel shackle head, helping mainsheet, halyard, vang, and spinnaker control lines run efficiently while allowing the block to align naturally with changing line angles.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eSheaves supported by Acetal or Torlon ball bearings deliver high-performance, low-friction operation. The two-stage ball bearing system provides consistent performance across the full load range, making this double block a practical choice for sailing systems that require responsive trimming and reliable line movement. Its lightweight construction helps support efficient rigging without adding unnecessary weight to the system.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eCheek cut-outs provide convenient access for bearing maintenance, helping sailors service the block when needed. The swivel shackle head rotates through 360 degrees, allowing the block to orient with the line and helping reduce twists or awkward alignment during use. Whether installed for mainsheet control, halyard routing, vang systems, or spinnaker control lines, the RF40200 is built for versatile small-boat sailing applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow-friction Acetal or Torlon bearing system:\u003c\/strong\u003e Supports smooth, efficient sheave movement for responsive line handling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTwo-stage ball bearing system:\u003c\/strong\u003e Provides consistent performance across the full load range.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLightweight design:\u003c\/strong\u003e Helps maintain an efficient sailing and rigging setup.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek cut-outs:\u003c\/strong\u003e Provide access for easier bearing maintenance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e360-degree swivel shackle head:\u003c\/strong\u003e Allows the block to align with changing line directions.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e Series 40\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e RF40200\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBlock configuration:\u003c\/strong\u003e Double block with swivel head\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearing type:\u003c\/strong\u003e Acetal or Torlon ball bearing system\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntended applications:\u003c\/strong\u003e Mainsheet, halyard, vang, and spinnaker control lines\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecommended vessel type:\u003c\/strong\u003e Off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF40200 Series 40 Double Ball Bearing Block for smooth, adaptable line control in demanding small-boat sailing applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Ronstan RF40200 Series 40 double ball bearing block with 360-degree swivel head for smooth, low-friction line control on boats up to 26 feet.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLow-friction Acetal or Torlon ball bearing system for smooth, efficient line handling.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eTwo-stage ball bearing system provides consistent performance across the full load range.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLightweight construction supports an efficient sailing and rigging setup.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCheek cut-outs allow easier access for bearing maintenance.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003e360-degree swivel shackle head helps the block align with changing line directions.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881671225433,"sku":"70616","price":84.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70616XL.jpg?v=1789193718"},{"product_id":"ronstan-rf40171-series-40-ball-bearing-block-single-upright-lead","title":"Ronstan RF40171 Series 40 Ball Bearing Block – Single Upright Lead","description":"\u003cp\u003e\u003cstrong\u003eSeries 40 Ball Bearing Block - Single Upright Lead\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eLead blocks are a low profile solution for leading halyards or other rig sail controls back to cleats or jammers. Precision molded Acetal sheaves running on Acetal or Torlon ball bearings provide high performance  low friction. The 2-stage ball bearing system provides consistent performance over the full load range.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eTypically used for halyards at the mast base.\u003c\/li\u003e\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eAcetal ball bearings\u003c\/li\u003e\n\u003cli\u003eUV stabilized Acetal sheave\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel load housing\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF40171 Series 40 Ball Bearing Block – Single Upright Lead\u003c\/strong\u003e provides a low-profile solution for leading halyards and other sail-control lines back to cleats or jammers. Designed for sailors, riggers, and boat owners, this Series 40 ball bearing block supports efficient line routing in applications where dependable, low-friction performance and a compact profile are important.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe precision-molded Acetal sheave runs on Acetal ball bearings to help deliver smooth line movement and high performance. Its two-stage ball bearing system is designed to provide consistent performance across the full load range, making the block well suited for sailboat rigging systems. The single upright lead configuration is typically used for halyards at the mast base, helping route control lines toward accessible deck hardware.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Low-profile design:\u003c\/strong\u003e Provides a compact solution for leading halyards and other sail controls back to cleats or jammers.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Two-stage ball bearing system:\u003c\/strong\u003e Supports consistent performance across the full load range.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Precision-molded Acetal sheave:\u003c\/strong\u003e Promotes high-performance, low-friction line handling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Single upright lead configuration:\u003c\/strong\u003e Suited to typical halyard routing applications at the mast base.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature: Marine-grade construction:\u003c\/strong\u003e Combines an UV-stabilized Acetal sheave with a Grade 316 stainless steel load housing.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e RF40171\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Series 40 ball bearing block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e Single upright lead\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrimary Application:\u003c\/strong\u003e Halyards at the mast base\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave Material:\u003c\/strong\u003e UV-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearing Material:\u003c\/strong\u003e Acetal ball bearings\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoad Housing:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF40171 Series 40 Ball Bearing Block for streamlined halyard routing and reliable low-friction performance in sailboat rigging applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Shop the Ronstan RF40171 Series 40 ball bearing block with a low-profile design, Acetal sheave, and two-stage bearings for halyard routing.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLow-profile design for leading halyards and other sail controls back to cleats or jammers.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eTwo-stage ball bearing system for consistent performance across the full load range.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003ePrecision-molded Acetal sheave for high-performance, low-friction line handling.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSingle upright lead configuration typically used for halyards at the mast base.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eUV-stabilized Acetal sheave and Grade 316 stainless steel load housing.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881671258201,"sku":"70615","price":68.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70615XL.jpg?v=1789193725"},{"product_id":"ronstan-rf41811-series-40-all-purpose-block-single-cheek","title":"Ronstan RF41811 Series 40 All Purpose Block, Single Cheek","description":"\u003cp\u003e\u003cstrong\u003eSeries 40 All Purpose Block - Single Cheek\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance, long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating sheave\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.Can be mounted on masts and booms using the curved surface adapter. Can be stacked to create a double version, but no more than 60% of the rated working load should be applied to the upper sheave. Stackable with Ronstan Series 40 deck organizers.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet\u003c\/li\u003e\n\u003cli\u003eHalyard\u003c\/li\u003e\n\u003cli\u003eVang\u003c\/li\u003e\n\u003cli\u003eSpinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU.V. stabilised Acetal sheaves\u003c\/li\u003e\n\u003cli\u003eImpact and U.V. resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel bearing race\u003c\/li\u003e\n\u003cli\u003eAlloy cheek plates\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan Series 40 All Purpose Block - Single Cheek\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eDesigned for sailors who need a versatile, durable solution for onboard line control, the Ronstan RF41811 Series 40 All Purpose Block delivers dependable performance for cruising and racing applications. Its self-lubricating Acetal polymer sheave runs on polished Grade 316 stainless steel races, allowing the block to perform effectively with both dynamic and high static loads. Use it for mainsheets, halyards, vangs, and spinnaker control lines on off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe single-cheek block is built for low maintenance and long service life in demanding sailing environments. It can be mounted on masts and booms with the appropriate curved surface adapter, stacked to create a double block, or combined with Ronstan Series 40 deck organizers. When stacked, no more than 60% of the rated working load should be applied to the upper sheave. This flexible design makes the RF41811 a practical choice when configuring reliable control-line systems for a wide range of sailing setups.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Exceptionally high working loads support demanding sheet, halyard, vang, and control-line applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Self-lubricating Acetal polymer sheave helps provide low-maintenance operation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Polished Grade 316 stainless steel bearing race supports smooth operation under dynamic and high static loads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Stackable design can create a double block and is compatible with Ronstan Series 40 deck organizers.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFeature:\u003c\/strong\u003e Mounting capability with a curved surface adapter allows installation on masts and booms.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e RF41811\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 40 All Purpose Block, single cheek\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave material:\u003c\/strong\u003e UV-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek material:\u003c\/strong\u003e Impact- and UV-resistant, fiber-reinforced Nylon\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearing race:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdditional material:\u003c\/strong\u003e Alloy cheek plates\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplications:\u003c\/strong\u003e Mainsheet, halyard, vang, and spinnaker control lines\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecommended boat use:\u003c\/strong\u003e Off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF41811 Series 40 All Purpose Block for a durable, adaptable component in your sailing control-line system.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO Meta Description:\u003c\/strong\u003e Shop the Ronstan RF41811 Series 40 All Purpose Block for sailing control lines, featuring a self-lubricating sheave and durable construction.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eExceptionally high working loads support demanding sheet, halyard, vang, and control-line applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSelf-lubricating Acetal polymer sheave helps provide low-maintenance operation.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003ePolished Grade 316 stainless steel bearing race supports smooth operation under dynamic and high static loads.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eStackable design can create a double block and is compatible with Ronstan Series 40 deck organizers.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eMounting capability with a curved surface adapter allows installation on masts and booms.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881671323737,"sku":"70607","price":98.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70607XL.jpg?v=1789193739"},{"product_id":"ronstan-rf41530-series-40-all-purpose-fiddle-becket-cleat-block","title":"Ronstan RF41530 Series 40 All Purpose Fiddle Becket Cleat Block","description":"\u003cp\u003e\u003cstrong\u003eSeries 40 All Purpose Block - Fiddle - Becket - Cleat\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance, long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating sheave\u003c\/li\u003e\n\u003cli\u003eCaptive Lock universal head\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003cli\u003eSnap fit removable becket pin\u003c\/li\u003e\n\u003cli\u003eMulti-position cleat arm\u003c\/li\u003e\n\u003cli\u003eSpare parts - RF41010 Replacement Becket Pin, RF150 Shackle\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.Captive Lock universal head can be fixed in either of two planes, or free to swivel as required. Quick adjusting cleat arms require no tools to adjust and fix securely in position. Becket pin is removable so line can be spliced prior to fitting.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet\u003c\/li\u003e\n\u003cli\u003eHalyard\u003c\/li\u003e\n\u003cli\u003eVang\u003c\/li\u003e\n\u003cli\u003eSpinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft)\u003c\/li\u003e\n\u003cli\u003eIdeal for fine-tune mainsheet tackles, cunninghams, backstays and other control line purchase systems.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU.V. stabilised Acetal sheaves\u003c\/li\u003e\n\u003cli\u003eImpact and U.V. resistant, fibre reinforced Nylon cheeks\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel bearing race\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel load strap and head fitting\u003c\/li\u003e\n\u003cli\u003eImpact and UV resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF41530 Series 40 All Purpose Block\u003c\/strong\u003e is a versatile fiddle block with a becket and cleat designed for sailors who need dependable control line handling on cruising and racing boats. Its durable construction, high working loads, and adaptable hardware make it suitable for mainsheets, halyards, vangs, spinnaker control lines, and fine-tune purchase systems.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKEY FEATURES:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh working loads:\u003c\/strong\u003e Built to handle demanding dynamic and static loads in a variety of sailing applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSelf-lubricating sheave:\u003c\/strong\u003e Acetal polymer sheave runs on polished stainless steel races for smooth, low-maintenance operation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCaptive Lock universal head:\u003c\/strong\u003e Fixes in either of two planes or swivels freely as needed for flexible installation and line control.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdjustable cleat arm:\u003c\/strong\u003e Multi-position cleat arm adjusts without tools and secures firmly in the selected position.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSlotted pin shackle:\u003c\/strong\u003e Helps reduce fouled lines while providing a practical connection point.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemovable becket pin:\u003c\/strong\u003e Snap-fit design allows line splicing before the block is installed.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003ePRODUCT DETAILS:\u003c\/strong\u003e\u003c\/p\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Ronstan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e RF41530\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Series 40 all purpose fiddle block with becket and cleat\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSheave material:\u003c\/strong\u003e U.V.-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheek material:\u003c\/strong\u003e Impact- and U.V.-resistant, fiber-reinforced Nylon\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearing race:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoad strap and head fitting:\u003c\/strong\u003e Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRecommended applications:\u003c\/strong\u003e Mainsheets, halyards, vangs, spinnaker control lines, cunninghams, backstays, and other control line purchase systems\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSuitable sailing uses:\u003c\/strong\u003e Off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReplacement parts:\u003c\/strong\u003e RF41010 replacement becket pin and RF150 shackle\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF41530 when you need an adaptable fiddle block that combines a becket, cleat, and universal head in one practical sailing hardware solution. It is a reliable choice for organizing and fine-tuning control lines on cruising and racing sailboats.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO META DESCRIPTION:\u003c\/strong\u003e Ronstan RF41530 Series 40 all purpose fiddle block with becket and cleat delivers versatile, low-maintenance control for sheets, halyards, and lines.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eExceptionally high working loads for demanding dynamic and static sailing applications\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSelf-lubricating Acetal sheave running on polished stainless steel races\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCaptive Lock universal head fixes in two planes or swivels as required\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eMulti-position cleat arm adjusts without tools and locks securely\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSlotted pin shackle helps eliminate fouled lines\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSnap-fit removable becket pin allows line splicing before installation\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881671389273,"sku":"70606","price":122.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70606XL.jpg?v=1789193751"},{"product_id":"ronstan-rf41300-series-40-triple-all-purpose-block-with-swivel-head","title":"Ronstan RF41300 Series 40 Triple All Purpose Block with Swivel Head","description":"\u003cp\u003e\u003cstrong\u003eSeries 40 All Purpose Block - Triple - Swivel Head\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance, long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating sheave\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003cli\u003eTwo way head post\u003c\/li\u003e\n\u003cli\u003eSpare parts - RF41010 Replacement Becket Pin, RF150 Shackle\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet\u003c\/li\u003e\n\u003cli\u003eHalyard\u003c\/li\u003e\n\u003cli\u003eVang\u003c\/li\u003e\n\u003cli\u003eSpinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eMaterials:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU.V. stabilised Acetal sheaves\u003c\/li\u003e\n\u003cli\u003eImpact and U.V. resistant, fibre reinforced Nylon cheeks\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel bearing race\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel load strap and head fitting\u003c\/li\u003e\n\u003cli\u003eSheave: UV stabilised acetal\u003c\/li\u003e\n\u003cli\u003eCheeks: Impact modified, fiber reinforced and UV stabilized nylon\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cstrong\u003eRonstan RF41300 Series 40 Triple All Purpose Block with Swivel Head\u003c\/strong\u003e is a durable marine line-handling block designed for cruising sailors, racing crews, one-design classes, sportsboats, and off-the-beach catamarans up to 26 feet. Its triple-sheave configuration supports mainsheet, halyard, vang, and spinnaker control line applications, while the swivel head helps provide versatile line direction and routing on deck.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eBuilt for demanding sailing environments, this all purpose block combines self-lubricating Acetal polymer sheaves with polished stainless steel races. The design performs with both dynamic loads and high static loads, making it a practical choice for frequently adjusted control lines as well as applications requiring dependable load handling. UV-stabilized materials and stainless steel components support low maintenance and a long service life in marine use.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe slotted pin shackle helps eliminate fouled lines, while the two-way head post supports flexible installation and operation. An impact- and UV-resistant, fiber-reinforced Nylon cheek construction adds durability to the block assembly. The Grade 316 stainless steel bearing race, load strap, and head fitting provide corrosion-resistant metal components for sailing applications. Spare parts are available separately, including the RF41010 Replacement Becket Pin and RF150 Shackle.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads for demanding sheet, halyard, and control line applications\u003c\/li\u003e\n\u003cli\u003eTriple self-lubricating Acetal sheaves running on polished stainless steel races\u003c\/li\u003e\n\u003cli\u003eSwivel head with two-way head post for flexible line alignment\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle helps eliminate fouled lines\u003c\/li\u003e\n\u003cli\u003eUV-stabilized, impact-resistant construction for cruising and racing use\u003c\/li\u003e\n\u003cli\u003eLow-maintenance design intended for a long service life\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eProduct Details:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBrand: Ronstan\u003c\/li\u003e\n\u003cli\u003eSeries: 40\u003c\/li\u003e\n\u003cli\u003ePart Number: RF41300\u003c\/li\u003e\n\u003cli\u003eProduct Type: Triple all purpose block with swivel head\u003c\/li\u003e\n\u003cli\u003eSheaves: UV-stabilized Acetal\u003c\/li\u003e\n\u003cli\u003eCheeks: Impact-modified, fiber-reinforced, UV-stabilized Nylon\u003c\/li\u003e\n\u003cli\u003eBearing race, load strap, and head fitting: Grade 316 stainless steel\u003c\/li\u003e\n\u003cli\u003eApplications: Mainsheet, halyard, vang, and spinnaker control lines\u003c\/li\u003e\n\u003cli\u003eIntended use: Off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet\u003c\/li\u003e\n\u003cli\u003eReplacement parts: RF41010 Replacement Becket Pin and RF150 Shackle\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003eChoose the Ronstan RF41300 for a versatile, durable block solution built to support reliable line handling across a wide range of sailing applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eSEO META DESCRIPTION:\u003c\/strong\u003e Shop the Ronstan RF41300 Series 40 triple swivel head block for durable, low-maintenance line handling on cruising and racing sailboats.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eWorking Load: Designed to accommodate exceptionally high working loads in demanding sailing applications.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eTriple Sheaves: Self-lubricating UV-stabilized Acetal sheaves run on polished Grade 316 stainless steel races.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSwivel Head: Two-way head post supports flexible line direction and routing.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSlotted Pin Shackle: Helps eliminate fouled lines during use.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eDurable Construction: Impact- and UV-resistant fiber-reinforced Nylon cheeks with Grade 316 stainless steel load components.\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSailing Applications: Suitable for mainsheets, halyards, vangs, and spinnaker control lines on boats up to 26 feet.\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881671651417,"sku":"70600","price":93.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/70600XL.jpg?v=1789193766"},{"product_id":"ronstan-rf41200-series-40-double-all-purpose-block-with-full-swivel-head","title":"Ronstan RF41200 Series 40 Double All Purpose Block with Full Swivel Head","description":"\u003cb\u003eSeries 40 All Purpose Block - Double Block - Full Swivel Head\u003c\/b\u003e\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\u003cp\u003eAll purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing. Head swivels freely.\u003cbr\u003e\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003cbr\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads\u003c\/li\u003e\n\u003cli\u003eLow maintenance, long service life\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating sheave\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle eliminates fouled lines\u003c\/li\u003e\n\u003cli\u003eTwo way head post\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eApplications:\u003c\/b\u003e\u003cbr\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMainsheet\u003c\/li\u003e\n\u003cli\u003eHalyard\u003c\/li\u003e\n\u003cli\u003eVang\u003c\/li\u003e\n\u003cli\u003eSpinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8M(26')\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eMaterials:\u003c\/b\u003e\u003cbr\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eU.V. stabilized Acetal sheaves\u003c\/li\u003e\n\u003cli\u003eImpact and U.V. resistant, fiber reinforced Nylon cheeks\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel bearing race\u003c\/li\u003e\n\u003cli\u003eGrade 316 stainless steel load strap and head fitting\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eSpecifications:\u003c\/b\u003e\u003cbr\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSheave : 40mm(1-9\/16\")\u003c\/li\u003e\n\u003cli\u003eMax. Rope : 10mm(7\/16\")\u003c\/li\u003e\n\u003cli\u003ePin : 5mm(3\/16\")\u003c\/li\u003e\n\u003cli\u003eM.W.L.: 600kg(1,320lbs)\u003c\/li\u003e\n\u003cli\u003eB. L.: 1,200kg(2,650lbs)\u003c\/li\u003e\n\u003cli\u003eWeight: 135g(4.8oz)\u003c\/li\u003e\n\u003c\/ul\u003e \u003c!--- cis2:m2lsl5xp ---\u003e\n\u003cp\u003e\u003cb\u003eRonstan Series 40 All Purpose Double Block with Full Swivel Head\u003c\/b\u003e is a versatile sailing hardware solution for cruising sailors, racers, and performance boats requiring dependable sheet, halyard, and control-line handling. The RF41200 combines a freely swiveling head with high working-load capability, low-maintenance construction, and durable materials for reliable service in a range of deck and rigging applications.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eSelf-lubricating Acetal polymer sheaves run on polished Grade 316 stainless steel bearing races to support both dynamic loads and high static loads. Impact- and UV-resistant, fiber-reinforced Nylon cheeks add durability, while the Grade 316 stainless steel load strap and head fitting provide a robust assembly. The slotted pin shackle helps reduce fouled lines, and the two-way head post allows the block to align effectively as loads change.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cb\u003eKey Features:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eExceptionally high working loads for demanding sheet, halyard, and control-line applications\u003c\/li\u003e\n\u003cli\u003eFull swivel head for flexible alignment under changing loads\u003c\/li\u003e\n\u003cli\u003eSelf-lubricating Acetal sheave for low-maintenance operation\u003c\/li\u003e\n\u003cli\u003eSlotted pin shackle helps eliminate fouled lines\u003c\/li\u003e\n\u003cli\u003eDurable UV-stabilized, impact-resistant materials for cruising and racing use\u003c\/li\u003e\n\u003cli\u003eTwo-way head post supports versatile rigging configurations\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cp\u003e\u003cb\u003eProduct Details:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eBrand: Ronstan\u003c\/li\u003e\n\u003cli\u003eModel: RF41200\u003c\/li\u003e\n\u003cli\u003eSeries: 40\u003c\/li\u003e\n\u003cli\u003eBlock type: Double all purpose block with full swivel head\u003c\/li\u003e\n\u003cli\u003eSheave: 1-9\/16 inches\u003c\/li\u003e\n\u003cli\u003eMaximum rope size: 7\/16 inch\u003c\/li\u003e\n\u003cli\u003ePin size: 3\/16 inch\u003c\/li\u003e\n\u003cli\u003eMaximum working load: 1,320 pounds\u003c\/li\u003e\n\u003cli\u003eBreaking load: 2,650 pounds\u003c\/li\u003e\n\u003cli\u003eWeight: 4.8 ounces\u003c\/li\u003e\n\u003cli\u003eApplications: Mainsheets, halyards, vangs, and spinnaker control lines on off-the-beach catamarans, one-design classes, and sportsboats up to 26 feet\u003c\/li\u003e\n\u003cli\u003eMaterials: UV-stabilized Acetal sheaves, impact- and UV-resistant fiber-reinforced Nylon cheeks, and Grade 316 stainless steel bearing race, load strap, and head fitting\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChoose the Ronstan RF41200 Series 40 Double All Purpose Block for durable, adaptable performance in sailing systems where smooth operation and dependable load handling matter.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e\u003cb\u003eSEO Meta Description:\u003c\/b\u003e Shop the Ronstan RF41200 Series 40 double block with full swivel head, self-lubricating sheave, and durable construction for sailing control lines.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eDouble all purpose block with full swivel head for flexible sailing-system alignment\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSelf-lubricating Acetal sheave runs on a polished Grade 316 stainless steel bearing race\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSupports a maximum working load of 1,320 pounds and a breaking load of 2,650 pounds\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSlotted pin shackle helps prevent fouled lines\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eUV-stabilized and impact-resistant materials support long service life\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eDesigned for mainsheets, halyards, vangs, and spinnaker control lines\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\u003ctd\u003eTruck Freight: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eOversized: No\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44881686921305,"sku":"65757","price":67.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/65757XL.jpg?v=1789194439"}],"url":"https:\/\/www.marinepartsonly.com\/collections\/blocks.oembed","provider":"Marine Parts Only","version":"1.0","type":"link"}