• Harken 57mm Carbo Air Block with Swivel, High-Strength & Low-Friction
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Harken

Harken 57mm Carbo Air Block with Swivel, High-Strength & Low-Friction

Harken 57mm Carbo Air Block with Swivel, High-Strength & Low-Friction

SKUCT-108339

$55.95
$55.95
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Product details

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Experience superior performance and durability with the Harken 57mm Carbo Air Block with Swivel. Engineered for efficient sail trimming, this lightweight and strong block delivers low-friction operation for fast trim and release, making it a reliable and affordable choice for any sailor. Its open-air design strategically eliminates unnecessary material, contributing to a lighter assembly without compromising strength. Upgrade your rigging with Harken's innovative design for safe, easy sailing.

Key Benefits & Features:

  • Low-Friction Efficiency: Free-running ball bearings roll on curved races, efficiently dispersing load for fast trimming and smooth line handling.
  • Lightweight & Strong Design: Up to 30% lighter and boasts a 60% higher working load than Harken's Classic blocks, thanks to its open-air design and glass fiber-reinforced nylon resin sideplates.
  • UV-Stabilized Durability: Ball bearings, sheave, and side plates are UV-stabilized with carbon black, offering maximum protection against harsh marine environments.
  • Versatile Swivel Head: A patented switch allows the shackle to lock in front or side positions, or swivel freely to prevent line twisting.

Specifications:

  • Sheave Diameter: 57mm (2-1/4in) for smooth line passage.
  • Maximum Line Diameter: Accommodates lines up to 10mm (3/8in) for broad compatibility.
  • Maximum Working Load: 359kg (792lb) ensures reliable performance under load.
  • Breaking Load: 1079kg (2380lb) for exceptional safety margins.
  • Length: 110mm (4-5/16in) compact design.
  • Weight: 87g (3.1oz) minimizes overall rigging weight.
  • Shackle Pin: 5mm (3/16in) for secure attachment.

Recommended Applications:

  • Ideal for main/jib sheets, mainsheet fine-tune, control lines, vangs, cunninghams, and outhauls.
  • Commonly used on centerboard and keelboats such as Lightnings, Dragons, Solings, and J/24's, as well as mainsheet systems on catamarans.
  • Specific one-design applications include Flying Scot Mainsheet Boom Block and MC Scow Boom Block (Foreward).

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