57mm Carbo Ratchamatic Flip-Flop Block with Cam
Mouse Over to Zoom
Click to Enlarge

HARKEN57mm Carbo Ratchamatic Flip-Flop Block with Cam


Fulfilled from vendor
Model # 9485731 | Mfg # 2145UPC # 97653177852


57mm Carbo Ratchamatic Flip-Flop Block with Cam

Name Value
Becket No Becket
Diameter 3/8 Inch or 10 mm
Direction Any
Integral Cleat Integral Cam
Length 4 5/16 Inches
Mount Type Mechanical Fasteners
Ratchet Ratcheting
Safe Working Load 300 Pounds
Sheave Diameter 57 mm
Type Single Pivoting
Weight 12 Ounces

Product Overview

Small Boat Flip-Flop Ratchamatic block with Cam pivots around the line axis to keep the line close to the deck. 

Harken's high-load Flip-Flop Block has a low profile, lightweight pivoting lead that articulates from side to side. Its hinged construction allows for various lead angles in mainsheet systems, mast-base control lines and spinnaker halyards, keeping lines clean and close to the deck. Ratchamatic feature gives sailors the holding power of up to 15:1. Ratchet can be adjusted to higher or lower load depending on the sailor's strength, sailing style and system usage.

The Ratchamatic Flip-Flop is a load-sensing  ratchet block that rolls freely in both directions under low loads and automatically engages the ratchet as loads increase.

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 Flip-Flop blocks are for halyard leads or mainsheet leads. 

Key Features

  • Hinged construction allows for various lead angles
  • Aluminum hardcoat-anodized side plates 
  • Adjustable ratchet at higher or lower loads
  • Ratchamatic blocks are hand and crew savers
  • Allows a line to be eased instantly with control 
  • Hardkote-anodized aluminum sheaves
  • Sheave Diameter: 2 1/4" (57 mm)
  • Max. Line Diameter: 3/8" (10 mm) 
  • Max. Working Load (MWL): 300 lb. (136 kg)   
  • Breaking Load: 600 lb. (272 kg)
  • Weight: 12 oz. (329 g)
  • Length: 4 5/16" (110 mm)


The West Advisor articles have answered boaters' questions and provided solutions to boating problems for more than 20 years. West Marine has compiled one of the Web's most comprehensive collections of technical boating information articles.

Related West Advisor Articles


Product Q & A