Use ball bearing bullet blocks to lead control lines with a minimum of friction. A wide range of variations let these versatile blocks adapt to almost all control line situations. Wire blocks use higher load carrying roller bearings, and feature teflon impregnated hardkote anodized aluminum sheaves. Use for halyards and other small boat wire controls. USE FOR: outhauls, vangs, barberhaulers, cunninghams, traveller controls, furling line leads, flag halyards. Sheave dia. 1-1/8-inch. Max. line : 5/16-inch. Breaking strength: 2000 lbs.