Unwrought or semi-wrought iron; unwrought or semi-wrought iron alloy; unwrought or semi-wrought steel; steel in sheet, pipe, tube, plate, bar, billet, bloom, slab and rail form; steel pipes and tubes for pipelines; nonferrous common metals and their alloys; unwrought or semi-wrought nonferrous metals and their alloys; building and construction materials of metal; prefabricated buildings of metal; valves of metal, other than parts of machine; metal junctions for pipes and tubes; metal flanges; small items of metal hardware, screws, nuts, nails, bolts and wedges of metal