Harken 57mm Aluminum Block — Swivel, Becket RHKYC-Branded Sailing Clothing The patented bearing system uses

The patented bearing system uses stainless steel balls in a captive grooved race and has a 250 lb (113 kg) maximum working load

An integral headspacer prevents Hard Lube-anodized aluminum sideplates from deflecting and binding

The 061 stanchion mount base attaches blocks to 7/8 in or 1 in (22 or 25 mm) stanchions or pulpits and is often used to lead furling lines to the cockpit

Maximum line Ø (in)3/4 in

Maximum working load (lb)750 lb

Harken 57mm Aluminum Block — Swivel, Becket RHKYC-Branded Sailing Clothing The patented bearing system usesPart No. 3216 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 line from twisting. Torlon is a registered trademark of