{"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","url":"https:\/\/www.marinepartsonly.com\/products\/ronstan-rf40300-series-40-triple-ball-bearing-block-with-swivel-head","provider":"Marine Parts Only","version":"1.0","type":"link"}