{"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","url":"https:\/\/www.marinepartsonly.com\/products\/ronstan-series-50-all-purpose-double-block-rf51200-with-swivel-shackle","provider":"Marine Parts Only","version":"1.0","type":"link"}