Stanchion Mounted Plain Bearing Block A stanchion mounted block is a device which, as the name suggests, is typically mounted to the vertical stanchion on a yacht. It allows lines to then be led along the length of the boat without the need to fix anything on the deck. Most commonly used to guide a line from the genoa furler back to the cockpit. The sheave part of this product can be rotated to achieve the perfect lead angle for the line. Key FeaturesEasily fitted to stanchions or bars. Plain bearing sheave for low maintenance. articulating sheave to align with the line.