Made of steel with high hardness and durability Step radiator wrench attaches directly to a 1/2" ratchet wrench The radiator spud wrench fits the installation and removal of most pipe and radiator components, including radiator valves, return fittings, thermostats and drain fittings User-friendly design for easy use and efficient results 1/2", 3/8", 3/4", 1-1/4" Ratchet Socket Spanner, Manufacturer: Pffiocix