{"product_id":"harken-57mm-aluminum-low-load-black-magic-block-w-swivel","title":"Harken 57mm Aluminum Low Load Black Magic Block w\/Swivel – Marine Boat Replacement Part","description":"\u003cp\u003e\u003cstrong\u003eHarken 57mm Aluminum Low Load Black Magic Block w\/Swivel – Marine Boat Replacement Part\u003c\/strong\u003e is organized for lighting \u0026amp; visibility shoppers who need a clear, professional marine parts buying experience.\u003c\/p\u003e\u003cp\u003e57mm Aluminum Low Load Black Magic Block with Swivel Black Magic Air blocks are a top favorite of Big Boat performance racers and cruisers. These lightweight, free-running, powerful performers are used for sail controls that see lots of action: mainsheet, runner, halyard, and spinnaker systems. A center cage keeps Torlon® roller bearings separated and parallel to reduce friction. Shackle blocks lock in two directions or swivel to keep the line from twisting. Low-load blocks have red isolators. They use Torlon® rollers and 316 stainless steel shackles. Standard blocks have 17-4 PH stainless head posts. Torlon is a registered trademark of Solvay Advanced Polymers L.L.C. Specifications: Sheave:\u003c\/p\u003e\u003ch3\u003eFitment \u0026amp; Product Details\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eBrand \/ Manufacturer: Harken\u003c\/li\u003e\n\u003cli\u003eMaterial: stainless steel, aluminum\u003c\/li\u003e\n\u003cli\u003eColor: black, red\u003c\/li\u003e\n\u003c\/ul\u003e\u003cul\u003e\n\u003cli\u003eSearch-optimized by brand, system, part type, and fitment cues.\u003c\/li\u003e\n\u003cli\u003eVerify compatibility with your original part number, engine model, and application before ordering.\u003c\/li\u003e\n\u003cli\u003eBuilt for boat owners, e-commerce shoppers, and professional marine service teams.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Harken","offers":[{"title":"Default Title","offer_id":42612817625177,"sku":"93959","price":211.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0623\/1818\/2489\/files\/harken-57mm-aluminum-low-load-black-magic-block-wswivel-3671386.jpg?v=1761802094","url":"https:\/\/www.marinepartsonly.com\/products\/harken-57mm-aluminum-low-load-black-magic-block-w-swivel","provider":"Marine Parts Only","version":"1.0","type":"link"}