Ronstan Blocks Core (45mm)

A balanced design approach incorporating functionality, performance and style makes our Core Blocks™ the right choice for performance cruising or racing applications. A tuned 2-stage bearing system provides excellent performance across the full working load range with an integrated thrust bearing feature and the resilience to handle high dynamic or static loads. Acetal & aluminium sheave options, alloy cheeks and stainless fixings complete the durable package.

Dynamic and high static load performance:
Core Blocks™ incorporate our proven 2-stage bearing system.

Stage 1 – Under moderate loads, acetal ball bearings ensure minimum friction.

Stage 2 – Under heavy loads, where deformation of ball bearings alone would result in increased friction, a sliding acetal bearing on a polished stainless steel race takes over, maintaining low friction performance.

Additionally the ball bearings are configured to act as a thrust bearing between the sheave and cheeks, preventing the sheave from rubbing on the cheeks and causing friction when the line lead in and out of the block isn’t perfect; particularly important for foot blocks.

MAURIPRO Sailing, your direct access to Ronstan Core Blocks – 45 mm and all your other sailing and boating needs.