drain pipes of metal; drain traps (valves) of metal; drain covers of metal; drain gullies of metal; drains made of metal; floor drains of metal; drain channels of metal; drainage pipes of metal; water pipe valves (metal); drainage plates of metal; water pipe valves of metal; water pipes of metal; metal sieves being parts of drains; drain plugs of metal (building materials); pipes of metal; water-pipe valves of metal; metal pipe fittings