57mm Carbo Ratchamatic Single Block with Cam
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HARKEN57mm Carbo Ratchamatic Single Block with Cam


Fulfilled from vendor
Model # 6580369 | Mfg # 2627UPC # 97653113331


57mm Carbo Ratchamatic Single Block with Cam

Name Value
Ball Bearings Plastic
Becket No Becket
Diameter 3/8 Inch or 10 mm
Direction Any
Integral Cleat Integral Cam
Length 4 1/16 Inches
Mount Type Swivel Shackle
Ratchet Ratcheting
Safe Working Load 300 Pounds
Sheave Diameter 57 mm
Type Single
Weight 9.4 Ounces

Product Overview

Harken 57mm Carbo Ratchamatic Single Block with Cam arms can be locked in more than five positions for fair leads.

Carbo Ratchets allow sailors to hand-hold loaded lines and offer balance between holding power and controlled easing. Lightweight Carbo Ratchets are available in 40mm, 57mm and 75mm sizes. All the Carbo Ratchets feature a recessed On-Off switch that is easily operated from either side. The 40mm cam-arm versions work in ratchet mode only. Commonly 57mm blocks are for jibsheets and spinnakers on medium sized dinghies.  

The 40mm, 57mm and 75mm Carbo Ratchamatic® is adjustable for many applications and weather conditions. The load-sensing ratchet block rolls freely in both directions under low loads, then engages the ratchet automatically as loads increase. With 180 degree wrap, you get a 10:1 holding power. 

Key Features

  • Eight-facet sheave holds line securely
  • Ratchet Ratchamatic® blocks are hand and crew savers
  • Allows a line to be eased instantly with control 
  • On/Off switch allows the ratchet to be turned off in light air 
  • 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): 300 lb. (136 kg)   
  • Breaking Load: 750 lb. (340 kg)
  • Weight: 9.4 oz. (266 g)
  • Length: 4 1/16" (103 mm)


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