Lewmar 90mm Synchro Block - Single

The Lewmar 90mm Synchro Block - Single (SKU: CW94310) is a precision rigging component engineered for marine and automotive applications where load distribution and mechanical advantage are critical. Originally designed for sailing and mechanical systems, this single block delivers the controlled efficiency that serious vehicle enthusiasts appreciate when upgrading pulley systems, winch setups, or mechanical advantage rigging on custom builds. Whether you're installing a high-performance recovery system, retrofitting a pulley-based winch configuration, or engineering a custom mechanical advantage system, understanding how modern block geometry optimizes force transfer is essential to your project's success.

At the heart of the Lewmar 90mm Synchro Block lies a scientifically optimized block geometry paired with a Free-Spin bearing and self-aligning head that dramatically reduce friction and increase operational efficiency. The 90mm sheave diameter provides an ideal balance between load capacity and line speed, minimizing wear on rope or cable while maintaining smooth mechanical motion. This single-block configuration (one movable or fixed pulley) serves as the foundation for custom rigging systems where you need reliable, frictionless rotation under load. The compact footprint—measuring 4 x 2 x 7 inches and weighing only 1.5 lbs—makes integration into tight spaces practical without sacrificing durability or performance.

This block excels in vehicle recovery systems, custom winch installations, and mechanical advantage applications where load control and repeatability matter. Fabricators and restoration specialists routinely specify Lewmar blocks for their predictable performance and low maintenance overhead. The self-aligning head automatically compensates for slight misalignment between anchor points and the load, protecting both the block and your rigging from premature wear. Installation is straightforward: secure the block to your chosen anchor point using the integral attachment eye, ensure proper line routing through the sheave, and verify that the block can rotate freely before subjecting it to load. Pair this single block with additional blocks to create two-to-one, four-to-one, or higher mechanical advantage systems tailored to your specific recovery or lifting needs.