Super Bow Rollers protect your boat's hull while trailering and spin freely to reduce drag when launching your boat. 3-piece design delivers maximum protection. 1/2" shaft diameter. Nonmarring polyurethane rollers resist cuts, abrasions, sun, oil, gas, and salt. Fits 3" bracket. 1/2" dia. shaft Nonmarring polyurethane rollers Fits 3" bracket | Super Bow Roller For 3" Bracket