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HARKEN 57mm Black Magic® Block, H/L Double

Model # 14135925Mfg # 3217


Customer Reviews
Delivery within 2 - 3 weeks.

Product Description

The entire line of Black Magic® AirBlocks® has been redesigned with a sleek new look. Their unique, performance-packed engineering remains exactly the same. These strong, lightweight blocks feature free-rolling, high-load Torlon® roller bearings for a high strength-to-weight ratio. Use them for sail controls that see lots of action: mainsheet, runner, halyard, and spinnaker systems.

  • Sheave: 6061-T6 Hardkote anodized aluminum
  • Bearings: Torlon® roller bearings, Carbon-black Delrin® ball bearings for side loads
  • Cheek Material/Finish: 6160-T6 Hardkote anodized aluminum
  • Construction: Dissimilar metals isolated for corrosion resistance. Easily disassembled
  • MWL (lb.): 3,600
  • Wt. (oz.): 10.1


57mm Black Magic® Block, H/L Double

Becket No Becket
Diameter 7/16 Inch or 11 mm
Sheave Diameter 57 mm
Direction Any
Integral Cleat No Integral Cleat
Length 5 3/16 Inches
Mount Type Swivel Shackle
Ratchet Non Ratcheting
Safe Working Load 3600 Pounds
Type Double
Weight 10.1 Ounces

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