Bosch Retaining Ring is designed for 1/2" electric drills, 3" X 21", 4" X 24" belt sanders, electric drywall drivers, laminate trimmers, plunge router, rotary hammers, screw drivers, self-tapping fastener driver, 1/2" drills, drywall drivers, fastener drivers, 3/8" tapper with auto rev, 1 3/4" SDS-max rotary hammer, chain saws, 220 - 240 V 1/2" high torque drill, 110 V high torque screwdrivers and Skil® routers.