Oil Filter Wrench 3/8" & 1/2" D.sq Drive - AK6403 Finish cast steel body with 3/8" and 1/2" square drives. Designed for use with ratchet wrench, but may also be used with a 21mm (13/16" ) spanner. • Extra wide nylon webbing strap. Capacity: <Ø300mm Drive: 3/8" & 1/2" & No.8221; Square