75mm Carbo Ratchamatic Single Block
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HARKEN75mm Carbo Ratchamatic Single Block


In stock online.
Model # 6840623 | Mfg # 2680UPC # 97653143710
75mm Carbo Ratchamatic Single Block




75mm Carbo Ratchamatic Single Block

Name Value
Ball Bearings Plastic
Becket No Becket
Diameter 7/16 Inch or 11 mm
Direction Any
Integral Cleat No Integral Cleat
Length 5 5/8 Inches
Mount Type Swivel Shackle
Ratchet Ratcheting
Safe Working Load 750 Pounds
Sheave Diameter 75 mm
Type Single
Weight 8.4 Ounces

Product Overview

Harken 75mm Carbo Ratchamatic Block with eight facet sheaves for a 10:1 purchase advantage. 

Carbo Ratchets blocks 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 75mm carbo ratchet blocks are for asymmetric spinnakers on medium keelboats.  

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

  • Hand-hold your loaded lines
  • Use for spinnaker sheet systems on dinghies, sportsboats, and medium keelboats
  • Ratchet 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 15/16" (75 mm)
  • Max. Line Diameter: 7/16" (12 mm) 
  • Max. Working Load (MWL): 750 lb. (341 kg)   
  • Breaking Load: 3000 lb. (1361 kg)
  • Weight: 8.4 oz. (238 g)
  • Length: 5 3/8" (137 mm)


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