Ronstan's award-winning Core Blocks high load blocks provide high performance and low friction. The anodized aluminum sheaves, high compression strength carbon black Acetal ball bearings, and the aluminum alloy cheek plates are designed to withstand use with wire running rigging. They have a tuned two-stage bearing system that provides excellent performance across the full working load range with an integrated thrust bearing feature and the resilience to handle dynamic or static loads.
The Series 45 Core Blocks are ideal for mainsheet, halyard, and spinnaker sheet applications on boats up to 33' (10m) and control line applications on larger yachts.
This Core Block has less than half the friction of its nearest competitor. This is a fully articulated stand-up model with a low-profile linkage that provides full rotation and articulation. A high-strength precision cast pad eye minimized the footprint and a dedicated rubber boot ensures the block is held upright when not rotated.