72mm Synchro Single Block
A unique block that is synchronized with running rigging systems.
The 72mm single block is a workhorse and can be used in a wide range of applications. The larger sheave diameter works well with up to 1/2" lines and is an excellent choice for halyard turning blocks, mainsheet systems, mast head block for external halyards and more.
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.
- 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
- Ideal for high static loads
- Mainsheet systems
- Boom vangs
- Halyard tuning systems
- Masthead blocks
- Standard equipment on newer racer/cruiser sailboats including Beneteau
|Sheave Diameter||Line Range||Shackle Post Pin Diameter|
72mm Synchro Single Block
|Diameter||1/2 Inch or 13 mm|
|Integral Cleat||No Integral Cleat|
|Mount Type||Swivel Shackle|
|Safe Working Load||2420 Pounds|
|Sheave Diameter||72 mm|
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