HARKEN 100mm Aluminum Double Block — Swivel, 3248 Sailing Shackles & Swivels_Loups Run multiple halyards and control

Run multiple halyards and control lines aft from the mast to stoppers or winches for quick easy adjustment

Sailors will appreciate the minimal stretch when the gloves get wet and how they dry soft to the touch

Lifetime warranty against breakage

UV-stable acetal sheaves provide durability for a long service life

Light but durable TPU fabric with fully welded construction

HARKEN 100mm Aluminum Double Block — Swivel, 3248 Sailing Shackles & Swivels_Loups Run multiple halyards and controlBlack 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. Offered in 57 150 mm sizes, with low load versions in 57 and 75 mm ranges. A center cage keeps Torlon roller bearings separated and parallel to reduce friction. The sheave center carries the primary load,