Aluminium cylinder head with cast iron cylinder gives added resistance to wear. Suitable for on site applications or anywhere that requires 110V. Especially useful for mandatory tyre pressure checks on site vehicles. One displays the tank pressure and the other displays the working pressures. Able to inflate and deflate tyres. Useful when deflating an over pumped tyre. Polyurethane recoil type hose helps to keep working area tidy and free of hoses when not in use.