{"product_id":"ronstan-series-55-ball-bearing-orbit-block-single-becket-with-swivel-head","title":"Ronstan Series 55 Ball Bearing Orbit Block - Single Becket with Swivel Head","description":"\u003cb\u003eSeries 55 Ball Bearing Orbit Block - Single - Becket - Swivel Head\u003c\/b\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eLightweight\u003c\/b\u003e\u003cbr\u003eKilogram for kilogram of working load, BB and RT Orbit Blocks are the world's lightest. The unique orbital design allows the bearing to only be in the active areas of the floating sheave. This minimises the mass of the inactive return race and hub.\u003cbr\u003e\u003cbr\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.\u003cbr\u003e\u003cbr\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.\u003cbr\u003e \u003cbr\u003e\u003cb\u003eHighest Working Load In Its Class\u003c\/b\u003e\u003cbr\u003eThe orbital ball-bearing arrangement gives the largest possible bearing race diameter. This maximises 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. \u003cbr\u003e\u003cbr\u003eThe floating sheave and bearing system is supported by a fiber-reinforced load frame. The design was computer modelled to be stress optimised. The Dyneema Link is produced from FSE Robline SK75 fiber, which is 10 times stronger and lighter than steel, and provides the final connection from the block to the load point.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003eUltra Lightweight\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eLow friction 2-stage Orbital ball bearing system\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eHighest working load in its class\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eLow profile and compact\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eHigh performance cleating\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eSwivel shackle head for unlimited block rotation\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eStainless steel shackle head for ultimate durability and compatibility with harsh fixing points\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eUltra low profile integrated becket\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eApplications:\u003c\/b\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003eMainsheet systems on dinghies, sportsboats and small keelboats to 9M(30')\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eSpinnaker sheets on dinghies, sportsboats and small keel boats to 9M(30')\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eHalyard, Vang and Backstay application on boats to 8M(26')\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eControl line applications on larger yachts\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eIdeal use for mainsheet systems and spinnaker sheets on dinghies, sportsboats and small keel boats to 9M(30')\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eAlso ideal with halyard, vang and backstay applications on boats to 8M(26')\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eSpinnaker sheets on sportsboats and small keel boats (lateral lead blocks)\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eControl line applications on larger yachts\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eMaterials:\u003c\/b\u003e\u003cbr\u003e\u003cul\u003e\n\u003cli\u003eBall bearings - High compression strength carbon black Acetal\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eStage 2 bearing - Carbon fiber reinforced, PTFE impregnated Nylon\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eFrame\/Cheeks - Toughened, glass fiber reinforced Nylon\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eRope Link: UV stabilized, multi-strand impregmented SK75 Dyneema\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eSheave: Carbon fiber reinforced, PTFE impregnated Nylon\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eHead fitting: Grade 316 stainless steel.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eSpecifications:\u003c\/b\u003e\u003cbr\u003e\u003cb\u003eSheave :\u003c\/b\u003e\t55mm(2-5\/32\")\u003cbr\u003e\u003cb\u003eMax. Rope :\u003c\/b\u003e    10mm(3\/8\")\u003cbr\u003e\u003cb\u003eM.W.L.:\u003c\/b\u003e\t500kg(1,100lbs)\u003cbr\u003e\u003cb\u003eB. L.:\u003c\/b\u003e\t1,000kg(2,200lbs)\u003cbr\u003e\u003cb\u003eWeight:\u003c\/b\u003e\t88g(3.1oz) \u003c!--- cis2:m2lumZRk ---\u003e\n\u003cp\u003eThe Ronstan Series 55 Ball Bearing Orbit Block with Single Becket and Swivel Head is designed for high-performance marine rigging systems. Its ultra-lightweight construction is achieved through a unique orbital bearing design that minimizes mass while maximizing load capacity. The ball bearings are positioned only in the active sheave areas, reducing unnecessary weight and ensuring smooth operation under heavy loads. This innovative design results in a lightweight, compact, and highly efficient block suitable for various sailing applications.\u003cbr\u003e \u003cbr\u003eConstructed with durable materials, the Series 55 Orbit Block features a 55mm sheave capable of handling ropes up to 3\/8 inch (10mm) in diameter. Its high compression grade acetal ball bearings provide low friction and excellent load distribution, supporting a maximum working load of 1,100 lbs (500kg) with a breaking load of 2,200 lbs (1,000kg). The floating sheave and bearing system are supported by a fiber-reinforced load frame, which has been stress-optimized through computer modeling for maximum strength and durability. The Dyneema Link, made from FSE Robline SK75 fiber, offers a lightweight yet incredibly strong connection, being ten times lighter than steel and resistant to harsh marine environments.\u003cbr\u003e \u003cbr\u003eThe block features a stainless steel swivel shackle head that allows for unlimited rotation, ensuring flexibility in rigging configurations. Its low-profile, compact design makes it ideal for applications such as mainsheet systems, spinnaker sheets, halyards, and control lines on boats up to 30 feet (9 meters). The high-performance cleating and integrated becket provide reliable operation and easy handling during sailing maneuvers. The materials used—such as carbon fiber reinforced Nylon, PTFE impregnated Nylon, and Grade 316 stainless steel—ensure longevity and resistance to corrosion, making it suitable for demanding marine conditions. This block is an excellent choice for sailors seeking a lightweight yet robust solution for their rigging needs, offering the highest working load in its class with minimal weight and maximum efficiency.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eUltra Lightweight construction for reduced weight and ease of handling\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eLow friction 2-stage orbital ball bearing system ensures smooth operation under load\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSupports highest working load in its class, maximizing safety and performance\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eCompact, low-profile design suitable for limited space applications\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eHigh performance cleating for secure line control\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eSwivel shackle head allows for unlimited rotation, increasing versatility\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eStainless steel shackle head for durability and compatibility with harsh environments\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eIntegrated becket for simplified line management\u003c\/li\u003e\u003c\/ul\u003e","brand":"Ronstan","offers":[{"title":"Default Title","offer_id":44529297391658,"sku":"55256","price":50.58,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0692\/2285\/8794\/files\/55256XL.jpg?v=1783070066","url":"https:\/\/atticusgoods.com\/products\/ronstan-series-55-ball-bearing-orbit-block-single-becket-with-swivel-head","provider":"Atticus Goods","version":"1.0","type":"link"}