57mm Carbo Ratchamatic Single Block
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HARKEN57mm Carbo Ratchamatic Single Block


In stock online.
Model # 2640043 | Mfg # 2625UPC # 97653103509


57mm Carbo Ratchamatic Single Block

Name Value
Ball Bearings Plastic
Becket No Becket
Diameter 3/8 Inch or 10 mm
Direction Any
Integral Cleat No Integral Cleat
Length 6 7/8 Inches
Mount Type Swivel Shackle
Ratchet Ratcheting
Safe Working Load 500 Pounds
Sheave Diameter 57 mm
Type Single
Weight 3.7 Ounces

Product Overview

Ease that sheet smoothly out in the lightest air, and get an automatic ratchet block when it's breeze on.

Shifting between ratchet and light-air modes is seamless. Harken 57mm Carbo Ratchamatic Single Block rolls freely in both directions under low loads and automatically engages the ratchet as loads increase. The 57mm load-sensing Carbo Ratchamatic® is adjustable for many applications and line loading conditions. With 180 degree wrap, you get a 10:1 holding power. Commonly 57mm blocks are for jibsheets and spinnakers on small dinghies.  

Key Features

  • Eight-facet sheave holds line securely
  • Load-sensing ratchet engagement can be adjusted with the included Allen wrench
  • Allows a line to be eased instantly with control 
  • Hardkote-anodized aluminum sheaves
  • Stainless steel swivel shackle
  • Sheave Diameter: 2 1/4" (57 mm)
  • Max. Line Diameter: 3/8" (10 mm) 
  • Max. Working Load (MWL): 500 lb. (227 kg)   
  • Breaking Load: 2000 lb. (907 kg)
  • Weight: 3.7 oz. (104 g)
  • Length: 4 1/16" (103 mm)


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