29mm Carbo Air® Double Block, Fixed
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HARKEN29mm Carbo Air® Double Block, Fixed

Model # 5367156 | Mfg # 381UPC # 97653134190

This item is no longer available.


29mm Carbo Air® Double Block, Fixed

Name Value
Ball Bearings Plastic
Becket No Becket
Diameter 5/16 Inch or 8 mm
Direction Any
Integral Cleat No Integral Cleat
Length 2 1/8 Inches
Mount Type Fixed Lashing Eye
Ratchet Non Ratcheting
Safe Working Load 660 Pounds
Sheave Diameter 29 mm
Type Double
Weight 1.2 Ounces

Product Overview

Harken 29mm Carbo Air® Double Block, Fixed allows a 2:1 or 3:1 purchasing system.

Low-friction Carbo AirBlocks® are lightweight, strong, reliable—and economical. Consistently 30% lighter and 60% stronger than equivalent Classic blocks. The sideplates are UV-stabilized, high-strength resin and designed for small-diameter lines favored by racers. Good for jib and mainsheet systems on high-performance dinghies, and for high-load control lines on small keelboats.

Recipient of both the Dame Award and Sail Magazine’s Freeman-Pittman Award for innovation, this innovative line of blocks turns fiber-reinforced composite construction into a reliable strength-to-weight ratio you can depend on. Companions to the popular Harken Black Magic block line, these small, compact blocks work well with very high working loads for easy trimming.

Key Features

  • High strength-to-weight ratio block
  • Harken’s most innovative blocks
  • 30% lighter, 60% stronger than equivalent conventional blocks
  • Smaller block for jib and mainsheet systems on high-performance dinghies 
  • Use for high-load control lines on small keelboats
  • Stainless steel swivel shackle
  • Sheave Diameter: 1 1/8" (29 mm)
  • Max. Line Diameter: 5/16" (8 mm)
  • Max. Working Load (MWL): 660 lb. (299 kg) 
  • Breaking Load: 1625 lb. (737 kg)
  • Weight: 1.2 oz. (34 g)
  • Length: 2 1/8" (54 mm)


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