BGS 5266 10-piece Special Twist Socket Set, 10-19 mm, 1/2″ Drive black bronzed surface for loosening damaged screws and nuts – suitable for impact wrenches the innovative spiral profile digs itself into the head of a damaged screw/nut and thereby allows to loosen it securely sizes: 10-11-12-13-14-15-16-17-19 mm with 1/2″ inch square drive