US PRO Air Powered Brake Piston Caliper Wind Back Tool 8595 A pneumatic/air tool for brake caliper piston rewind. For left and right hand threaded pistons. Suitable for most 3/8″ sq Dr wind-back adaptors and pin type adaptors. 1/4″ BSP High Flow air inlet bayonet fitting included. Supplied with a 3/8″ sq Dr to 2 pin magnetic adaptor.