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. With conventional blocks, one of the biggest losses in efficiency comes from the distortion of line as it wraps around the sheave. Synchro blocks provide the optimal ratio between line size, sheave diameter and the interface between rope and sheave. The result is larger sheaves with a smaller axle than exist on conventional blocks. Synchro blocks improve efficiency by nearly 5% on a single block at a load of 442lb. Calculated over a typical six-block mainsheet system, this approaches a 40% improvement over conventional blocks.
|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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Comments about Lewmar 72mm Synchro Single Block:
This is a great block for your mainsail boom if your sheet tends to twist under tension. This has a stop that you can set so that it can not rotate 360 degrees but is limited to about 20 degrees. This solved the twisting that was constricting my mainsail sheet.