72mm Synchro Block, Fiddle Becket with Cam
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LEWMAR72mm Synchro Block, Fiddle Becket with Cam


In stock online.
Model # 13062070 | Mfg # 29927239BKUPC # 743683203855


72mm Synchro Block, Fiddle Becket with Cam

Name Value
Becket Becket
Diameter 1/2 Inch or 13 mm
Direction Any
Integral Cleat Integral Cam
Mount Type Swivel Shackle
Ratchet Non Ratcheting
Safe Working Load 2420 Pounds
Sheave Diameter 72 mm
Type Single Fiddle
Weight 12.53 Ounces

Product Overview

A unique block that is synchronized with running rigging systems.

The 72mm fiddle becket with cam is ideal for mainsheet and vang systems and can be set up to offer a 4:1 purchase. The larger sheave diameter works well with up to 1/2" lines.

Synchro blocks combine geometry, sheave ratios and a unique Free Spin bearing to deliver performance that’s comparable to ball and roller bearing blocks used in racing—but at a more affordable price. Designed to optimize the relationship between block and line, these blocks have self-aligning features to maximize efficiency and reduce wear to both line and block. An innovative sliding mechanism controls shackle post swivel. With the flick of a switch select between full 360° free rotation or one of two fixed settings (0° or 90° to sheave axle). Both fixed positions provide 30° of rotational “float” to allow the block to self-align to the system.

Synchro blocks use a larger sheave that features the Free Spin bearing. The bigger diameter sheave prevents distortion and reduces line wear while the Free-Spin bearing handles higher static loads. A stainless steel shackle post and framework supports the glass fiber reinforced cheeks to increase block strength while minimizing overall weight. The molded cheeks guide the line and prevent wedging.

Designed to be synchronized with your boat’s running rigging systems, Lewmar Synchro blocks are an ideal choice for the sailor looking to get more for less: racing features at a cruising price.

Key Features

  • Plain bearing block with ball bearing like performance
  • Highly efficient free-spin bearing reduces drag
  • Self-aligning head allows 30° of float (in locked setting) to reduce wear on line
  • Stainless steel strap for added strength and durability
  • Adjustable swivel settings: full rotation, parallel with the pin and perpendicular with the pin
  • Stiff cheeks guide line to prevent wedging
  • Compatible with lines between 3/8"—1/2"
  • Standard equipment on newer racer/cruiser sailboats including Beneteau
  • Ideal for high static loads
    • Mainsheet systems
    • Boom vangs

Selection Guide

Sheave DiameterLine RangeShackle Swivel Post Pin Diameter
50mm1/4"—3/8" (6mm—10mm)3/32"
60mm5/16"—3/8" (8mm—10mm)3/16"
72mm3/8"—1/2" (10mm—12mm)1/4"
90mm1/2"—9/16" (12mm—14mm)3/8"


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