{"id":33383,"date":"2026-04-02T11:35:38","date_gmt":"2026-04-02T09:35:38","guid":{"rendered":"https:\/\/shopandsail.com\/?post_type=product&p=33383"},"modified":"2026-04-02T11:48:17","modified_gmt":"2026-04-02T09:48:17","slug":"31-friction-block-karver","status":"publish","type":"product","link":"https:\/\/shopandsail.com\/en\/shop\/fittings-en\/31-friction-block-karver\/","title":{"rendered":"3:1 friction block Karver"},"content":{"rendered":"
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Installing a furling system (such as a Code 0 or Gennaker) often requires significant force to achieve proper tension. The Karver 3:1 friction block is the essential accessory<\/strong> to simplify your maneuvers. It is perfectly suited for both small sailboats and catamarans up to 90 feet.<\/p>\n

Thanks to its 3:1 purchase system<\/strong>, this product reduces the force needed to tension the sail by three. This represents a major comfort gain, especially for sails with a mast hook where all tension adjustments are made from the bottom.<\/p>\n

This product comes in 5 versions<\/strong> (from KF1.5 to KF8.0) to match your boat. The KF1.5 model is ideal for sailboats from 10 to 40 feet, while the KF8.0 version offers a breaking load of 16.00T<\/strong>, making it suitable for larger vessels.<\/p>\n

Made from molded stainless steel<\/strong>, this friction block ensures excellent durability and total corrosion resistance. It is more compact and more affordable than a traditional pulley, while allowing you to bring the sail setup closer to you. This means you can avoid going forward on deck in rough conditions.<\/p>\n

Finally, its versatility allows it to be used as a 3:1 or 2:1 system<\/strong> depending on your needs. To complete your setup, explore our spare parts for your deck hardware.<\/p>\n

Technical specifications of the Karver 3:1 friction block:<\/strong><\/h6>\n
    \n
  • Variants: KF1.5, KF3.0, KF4.5, KF6.0, KF8.0<\/li>\n
  • Material: molded stainless steel (high-strength stainless steel)<\/li>\n
  • Compatibility: Karver furling systems and other brands<\/li>\n
  • Installation: mounting under the drum or on the swivel<\/li>\n<\/ul>\n\n\n\n\n\t\n\n\t\n\t\n\t\n\t\n\t
    Model<\/th>Working Load (T)<\/th>Breaking Load (T)<\/th>Weight (kg)<\/th>Sailboat Size<\/th>Dimensions H x L x W (mm)<\/th>\n<\/tr>\n<\/thead>\n
    KF1.5<\/td>1,50 T<\/td>3T<\/td>0,084<\/td>10 - 40 ft<\/td>41,5 x 26 x 39,6
    \r\n<\/td>\n<\/tr>\n
    KF3.0<\/td>3,00 T<\/td>6T<\/td>0,140<\/td>30 - 50 ft<\/td>54,4 x 40 x 31,8<\/td>\n<\/tr>\n
    KF4.5<\/td>4,50 T<\/td>9T<\/td>0,248<\/td>40 - 80 ft<\/td>75 x 39,7 x 48<\/td>\n<\/tr>\n
    KF6.0<\/td>6,00 T<\/td>12T<\/td>0,394<\/td>40 - 80 ft<\/td>77 x 57,1 x NC<\/td>\n<\/tr>\n
    KF8.0<\/td>8,00 T<\/td>16T<\/td>0,625<\/td>40 - 90 ft<\/td>92,7 x NC x 62<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
    <\/div>\n
    \n
    <\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<\/div>\n
    <\/div>\n","protected":false},"excerpt":{"rendered":"

    Discover the Karver 3:1 friction block<\/strong>, a high-performance adjustment solution for your furling system. Available for loads from 1.5T to 8T<\/strong>, this molded stainless steel accessory allows you to tension your sail effortlessly from the cockpit. Ideal for easy installation on a bowsprit.<\/p>\n

    Available in 5 versions, from KF1.5 to KF8.0.<\/strong><\/em><\/p>\n","protected":false},"featured_media":33366,"template":"","meta":{"_acf_changed":false,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kad_post_transparent":"default","_kad_post_title":"","_kad_post_layout":"default","_kad_post_sidebar_id":"","_kad_post_content_style":"default","_kad_post_vertical_padding":"default","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":""},"monocoques":[],"multicoques":[],"stock":[],"product_brand":[],"product_cat":[297,298,1203,1254],"product_tag":[],"product_brands":[1555],"class_list":{"0":"post-33383","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-fittings-en","7":"product_cat-deck-fittings-en","8":"product_cat-fairleads-sheaves-en","9":"product_cat-outdoor-equipment-en","10":"pa_charge-de-travail-tonne-1-5t-kf1-5-model","11":"pa_charge-de-travail-tonne-3t-kf3-0-model","12":"pa_charge-de-travail-tonne-4-5t-kf4-5-model","13":"pa_charge-de-travail-tonne-6t-kf6-0-model","14":"pa_charge-de-travail-tonne-8t-kf8-0-model","15":"product_brands-karver-en","17":"first","18":"onbackorder","19":"taxable","20":"shipping-taxable","21":"purchasable","22":"product-type-variable","23":"entry","24":"content-bg","25":"loop-entry"},"bundled_by":[],"bundle_stock_status":"onbackorder","bundle_stock_quantity":null,"bundle_virtual":false,"bundle_layout":"","bundle_add_to_cart_form_location":"","bundle_editable_in_cart":false,"bundle_sold_individually_context":"","bundle_item_grouping":"","bundle_min_size":"","bundle_max_size":"","bundle_price":[],"bundled_items":[],"bundle_sell_ids":[],"acf":[],"yoast_head":"\n3:1 friction block Karver - Shop and Sail<\/title>\n<meta name=\"description\" content=\"Improve your sail tension with the Karver 3:1 friction block. 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