Harken 57mm Aluminum Double Block — Swivel RHKYC-Branded Sailing Clothing Base Ø (in)4

Base Ø (in)4

Quantity25

UV-stabilized for excellent protection against long-term exposure to saltwater and sun

Weight (g)142 g

spring pin

Harken 57mm Aluminum Double Block — Swivel RHKYC-Branded Sailing Clothing Base Ø (in)4Part No. 3217 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