2:1 Halyard Shackle w/ Sheave - 3/8" - 9/16" Line, 0.32" Pin, 4,000 lb SWL

Tylaska Halyard Shackles have the highest strength-to-weight ratio of any existing halyard shackles. They are made of high strength aluminum and have a captive stainless steel cross-pin.

These "2:1" models with an integral free-rolling sheave are designed for a main halyard system with a 2:1 purchase for easier mainsail hoisting.

Mainsail halyard shackles provide a strong, fast, reliable means of attaching and releasing the mainsail halyard to the head of the sail.
Adequate room for easy-fitting to the headboard and an easy-to-engage, smoothly functioning screw-pin are of paramount importance.
Headboard shackles also prevent the bitter end of a loose halyard from inadvertantly unreeving by running through the sheave box at the top of the mast.

The clevis slot length and width of Tylaska Halyard Shackles are carefully designed and machined to fit standard headboards without adding unnecessary mass or weight.
The super-strong 17-4PH headboard pin resists wear and deformation, and is captive to avoid loss while the shackle is being attached. The pin is initially loose-fitting for easy engagement, but the fit tightens and secures as it is screwed in. When the pin is disengaged for attaching, the unique recessed thread design allows maximal clevis throat width for passing over the headboard or grommet.

• Free-rolling aluminum sheave reduces heat and wear on halyard in 2:1 purchase halyard systems
• Body machined from a solid block of aluminum
• Hard coat annodized for excellent corrosion resistance
• Strength and weight optimized via computer modeling and verified by destructive laboratory testing
• Every shackle is individually factory pull-tested