Harken 57mm Aluminum Low Load Black Magic Block w/Swivel

<p><strong>57mm Aluminum Low Load Black Magic Block with Swivel</strong></p><p>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. </p><p><strong>Specifications:</strong></p><ul><li>Sheave: 57mm/2-1/4in</li><li>Length: 119mm/4-11/16in</li><li>Weight: 154g/5.44oz</li><li>Shackle Pin: 6mm/1/4in</li><li>Maximum Line: 12mm / 7/16in</li><li>Maximum Working Load: 7/16kg / 1655lbs</li><li>Breaking Load: 1500kg / 3300lb</li></ul> <!--- cis2:mm5sl5hm --->