{"title":"Automatic Ratchet Blocks for Dinghies","description":"\u003cp\u003eSeldén automatic ratchet blocks in the ARB45 and A60 ranges, 45 mm and 60 mm sheave diameters with composite or aluminium sheaves, in swivel, soft attachment and cheek mounting options for dinghy mainsheets and spinnaker sheets.\u003c\/p\u003e\n\u003ch2\u003eHow to choose\u003c\/h2\u003e\n\u003cp\u003eAn automatic ratchet block switches from free-turning to ratchet mode as load increases, holding the line without the sailor needing to cleat it. Unlike a manual ratchet block where the sailor operates a switch, the automatic version engages on its own. The switchover point is adjustable with an allen key on all blocks in this collection, so the sailor sets the load threshold to match their conditions and preference.\u003c\/p\u003e\n\u003cp\u003eThe first choice is sheave size. The ARB45 has a 45 mm sheave and suits lines up to 8 mm, covering mainsheets and spinnaker sheets on smaller and mid-sized dinghies. The A60 and A60+ have a 60 mm sheave and suit lines up to 10 mm, providing lower friction under higher loads on larger dinghies and two-handed boats.\u003c\/p\u003e\n\u003cp\u003eWithin the A60 range, choose between the standard composite sheave (A60) and the aluminium sheave (A60+). The aluminium sheave provides more grip on the line, which is useful when running thinner mainsheet or sheet lines where the composite sheave gives less bite. If your sheet is at the upper end of the 10 mm range the composite sheave is sufficient. If you are running a finer line and want more positive ratchet engagement, the A60+ is worth specifying.\u003c\/p\u003e\n\u003cp\u003eFor mounting, choose between swivel\/fixed, soft attachment and cheek options. The swivel\/fixed shackle locks at 0° or 90° and suits transom or boom-end mainsheet fittings. The soft attachment versions mount with a soft shackle or Dyneema lashing, saving weight and eliminating a metal contact point. The cheek versions mount flush with three M5 screws and are directional: the clockwise version is for the starboard spinnaker sheet turning block, the anti-clockwise version is for port.\u003c\/p\u003e\n\n\u003ch2\u003eWhat's in this collection\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003eARB45\u003c\/strong\u003e is a 45 mm automatic ratchet block for lines up to 8 mm, suited to mainsheets and spinnaker\/gennaker sheets on smaller dinghies. It is available in two versions: a composite sheave swivel variant (404-401-01R) and an aluminium sheave variant (404-360-51), the latter providing more grip on finer lines. Both include a swivel lock for 0° or 90° fixed shackle position.\u003c\/p\u003e\n\u003cp\u003eThe \u003cstrong\u003eA60\u003c\/strong\u003e is a 60 mm automatic ratchet block with a composite sheave for lines up to 10 mm. Available as a swivel\/fixed variant (406-350-51R), a soft attachment version for use with a soft shackle or Dyneema lashing (406-350-54R), a clockwise cheek block for the starboard spinnaker sheet quarter (406-350-55R), and an anti-clockwise cheek block for the port spinnaker sheet quarter (406-350-56R).\u003c\/p\u003e\n\u003cp\u003eThe \u003cstrong\u003eA60+\u003c\/strong\u003e is the aluminium sheave version of the A60, providing more grip on thinner lines. Available as a swivel\/fixed variant (406-360-51R) and a soft attachment version (406-360-54R). Both suit lines up to 10 mm.\u003c\/p\u003e","products":[{"product_id":"a60-60-mm-automatic-ratchet-block-soft-attachment-1","title":"A60 - 60 mm Automatic Ratchet block, Soft-Attachment","description":"\u003cp\u003eTECHNICAL FEATURES\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eThe block is designed with lightweight Delrin ball bearings and comes with a composite sheave.\u003c\/li\u003e\n\u003cli\u003eThe sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in.\u003c\/li\u003e\n\u003cli\u003eThe switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.\u003c\/li\u003e\n\u003cli\u003eMade for soft-attachment with a soft-shackle or a Dyneema lashing. \u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eSafe working Load\u003c\/b\u003e: 250 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eBreaking Load\u003c\/b\u003e: 500 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eMax line size\u003c\/b\u003e: 10 \u003cem\u003emm\u003c\/em\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Selden Dinghy Store","offers":[{"title":"Default Title","offer_id":52013477101906,"sku":"406-350-54R","price":88.98,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0993\/1325\/4738\/files\/index_ae96c4ee-c39c-4188-b92b-ef9c202ed4b7.jpg?v=1763034997"},{"product_id":"a60-60-mm-automatic-ratchet-block-cheek-clockwise-1","title":"A60 - 60 mm Automatic Ratchet Block, Cheek, Clockwise","description":"\u003cp\u003eTECHNICAL FEATURES\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eThe block is designed with lightweight Delrin ball bearings and comes with a composite sheave.\u003c\/li\u003e\n\u003cli\u003eThe Sheave turns freely clockwise. When used as a turning block for spinnaker sheet, fit it on starboard quarter.\u003c\/li\u003e\n\u003cli\u003eThe sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in.\u003c\/li\u003e\n\u003cli\u003eThe switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.\u003c\/li\u003e\n\u003cli\u003eAttaches with three M5 screws.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eSafe working Load\u003c\/b\u003e: 250 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eBreaking Load\u003c\/b\u003e: 500 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eMax line size\u003c\/b\u003e: 10 \u003cem\u003emm\u003c\/em\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Selden Dinghy Store","offers":[{"title":"Default Title","offer_id":52013477593426,"sku":"406-350-55R","price":111.1,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0993\/1325\/4738\/files\/index_4e997d23-8565-4fed-afdd-694d672ffae5.jpg?v=1763034998"},{"product_id":"a60-60-mm-automatic-ratchet-block-cheek-anti-clockwise-1","title":"A60 - 60 mm Automatic Ratchet Block, Cheek, Anti-Clockwise","description":"\u003cp\u003eTECHNICAL FEATURES\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eThe block is designed with lightweight Delrin ball bearings and comes with a composite sheave.\u003c\/li\u003e\n\u003cli\u003eThe Sheave turns freely anti-clockwise. When used as a turning block for spinnaker sheet, fit it on port quarter.\u003c\/li\u003e\n\u003cli\u003eThe sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in.\u003c\/li\u003e\n\u003cli\u003eThe switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.\u003c\/li\u003e\n\u003cli\u003eAttaches with three M5 screws.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eSafe working Load\u003c\/b\u003e: 250 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eBreaking Load\u003c\/b\u003e: 500 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eMax line size\u003c\/b\u003e: 10 \u003cem\u003emm\u003c\/em\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Selden Dinghy Store","offers":[{"title":"Default Title","offer_id":52013484900690,"sku":"406-350-56R","price":111.1,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0993\/1325\/4738\/files\/index_37801095-68ac-413f-901f-710f91420ea3.jpg?v=1763035014"},{"product_id":"a60-60-mm-automatic-ratchet-block-with-aluminium-sheave-1","title":"A60+ - 60 mm Automatic Ratchet Block with Aluminium Sheave","description":"\u003cp\u003eThe automatic A60+ ratchet block is designed for dynamic applications on dinghies and keelboats and features a ø60 mm aluminium sheave. Aluminium makes for more grip and the ability to cope with relative thin lines.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eThe block is designed with lightweight Delrin ball bearings and the sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in.\u003c\/li\u003e\n\u003cli\u003eThe switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.\u003c\/li\u003e\n\u003cli\u003eA swivel lock, a plastic washer which is placed between block body and shackle, is included for fixed 0° or 90° shackle position.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eSafe working Load\u003c\/b\u003e: 250 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eBreaking Load\u003c\/b\u003e: 500 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eMax line size\u003c\/b\u003e: 10 \u003cem\u003emm\u003c\/em\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Selden Dinghy Store","offers":[{"title":"Default Title","offer_id":52013485261138,"sku":"406-360-51R","price":141.89,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0993\/1325\/4738\/files\/index_095ffd70-f3c0-4885-8e91-839212b2c37b.jpg?v=1763035016"},{"product_id":"a60-60-mm-automatic-ratchet-block-soft-attachment-aluminium-sheave-1","title":"A60+ - 60 mm Automatic Ratchet Block, Soft-attachment, Aluminium sheave","description":"\u003cp\u003eThe automatic A60+ ratchet block is designed for dynamic applications on dinghies and keelboats and features a ø60 mm aluminium sheave. Aluminium makes for more grip and the ability to cope with relative thin lines.\u003c\/p\u003e\u003cp\u003eTECHNICAL FEATURES\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eThe block is designed with lightweight Delrin ball bearings and comes with a composite sheave.\u003c\/li\u003e\n\u003cli\u003eThe sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in.\u003c\/li\u003e\n\u003cli\u003eThe switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.\u003c\/li\u003e\n\u003cli\u003eMade for soft-attachment with a soft-shackle or a Dyneema lashing. \u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eSafe working Load\u003c\/b\u003e: 250 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eBreaking Load\u003c\/b\u003e: 500 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eMax line size\u003c\/b\u003e: 10 \u003cem\u003emm\u003c\/em\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Selden Dinghy Store","offers":[{"title":"Default Title","offer_id":52013487620434,"sku":"406-360-54R","price":124.57,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0993\/1325\/4738\/files\/index_19f02e03-6642-4ef8-aecc-3aa393240406.jpg?v=1763035033"},{"product_id":"arb45-45-mm-automatic-ratchet-block-single-aluminium-sheave-1","title":"ARB45 - 45 mm Automatic Ratchet Block, Single, Aluminium sheave","description":"\u003cp\u003eAPPLICATIONS\u003cbr\u003eDinghy main sheets.\u003cbr\u003eDinghy spinnaker\/Gennaker sheets\u003c\/p\u003e\u003cp\u003e\u003cbr\u003eTECHNICAL FEATURES\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eThe block is designed with lightweight Delrin ball bearings and comes with an aluminium sheave for more grip when using it for a thin line. \u003c\/li\u003e\n\u003cli\u003eThe sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in.\u003c\/li\u003e\n\u003cli\u003eThe switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.\u003c\/li\u003e\n\u003cli\u003eThe shackle is either swiveling or locked in 0°\/90°. A swivel lock 404-131 is included when purchasing the block. \u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eSafe working Load\u003c\/b\u003e: 150 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eBreaking Load\u003c\/b\u003e: 300 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eMax line size\u003c\/b\u003e: 8 \u003cem\u003emm\u003c\/em\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Selden Dinghy Store","offers":[{"title":"Default Title","offer_id":52143058157906,"sku":"404-360-51","price":80.32,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0993\/1325\/4738\/files\/index_5a2efeab-7386-43c2-a892-6ab9f84cbb3d.jpg?v=1764239940"},{"product_id":"45-mm-automatic-ratchet-block-single-swivel-1","title":"45 mm Automatic Ratchet Block - Single, Swivel","description":"\u003cp\u003eThe ARB45 Single Swivel Block is a 45 mm ball bearing block with a swiveling shaft. A swivel lock, a plastic washer which is placed between block body and shackle, is included for fixed 0° or 90° shackle position.\u003c\/p\u003e\u003cp\u003eThe block is designed with lightweight ø5 mm Delrin ball bearings and features a composite sheave. The sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in. The switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e\u003cb\u003eSafe working Load\u003c\/b\u003e: 150 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eBreaking Load\u003c\/b\u003e: 300 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eMax line size\u003c\/b\u003e: 8 \u003cem\u003emm\u003c\/em\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Selden Dinghy Store","offers":[{"title":"Default Title","offer_id":52143058878802,"sku":"404-401-01R","price":73.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0993\/1325\/4738\/files\/index_d2824291-f5ca-49bd-9005-27680162b2af.jpg?v=1764239960"},{"product_id":"a60-60-mm-automatic-ratchet-block-single-swiveling-fixed-1","title":"A60 - 60 mm Automatic Ratchet block, Single, Swiveling\/Fixed","description":"\u003cp\u003eThe automatic A60 ratchet block is designed for dynamic applications on dinghies and keelboats and features a ø60 mm composite sheave. \u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eThe block is designed with lightweight Delrin ball bearings and the sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in.\u003c\/li\u003e\n\u003cli\u003eThe switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.\u003c\/li\u003e\n\u003cli\u003eA swivel lock, a plastic washer which is placed between block body and shackle, is included for fixed 0° or 90° shackle position.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cb\u003eSafe working Load\u003c\/b\u003e: 250 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eBreaking Load\u003c\/b\u003e: 500 \u003cem\u003ekg\u003c\/em\u003e\u003cbr\u003e\u003cb\u003eMax line size\u003c\/b\u003e: 10 \u003cem\u003emm\u003c\/em\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Selden Dinghy Store","offers":[{"title":"Default Title","offer_id":52143059140946,"sku":"406-350-51R","price":101.48,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0993\/1325\/4738\/files\/index_6b8f3320-7e25-469f-8c37-a02df1e3ac4a.jpg?v=1764239962"}],"url":"https:\/\/dinghy.seldenmast.com\/collections\/ratchet-automatic.oembed","provider":"Seldén Dinghy Store","version":"1.0","type":"link"}