Metals and metal alloys; fittings of metal for pipes; steel tubes; stainless steel pipes; metal pipes and tubes; tubes of metal; valves of metal, other than parts of machines; metal pipe couplings; joints of metal for pipes; metal flanges; elbows of metal for pipes; pipe connectors of metal for plumbing; water-pipe valves of metal; metal fittings for water-pipes; pipe fittings of stainless steel; metal tubing and tubing couplings of metal for joining and terminating pipes; tubes of stainless ...