6 Common metals and their alloys, unwrought or semi-wrought; metal hardware, namely, metal slides for doors and windows, metal rollers for doors and windows, window handles, hinges, door locks and window locks; Common metals, unwrought and semi-worked, for further manufacture; metal building materials, namely, shop window frames, shop window panes, window frames, window panes, window sills, window vents, window fittings, window trim, door frames, door knobs, door handles, door fittings, door trim, steel frames, steel brackets, steel in the form of plates, curtain walling frames, curtain walling panes; structures and transportable buildings of metal; ironmongery in the nature of small items of metal hardware for windows and doors, namely, side frames, end caps, spacers, crank handles, pull straps, side tracks, ball bearings and installation hardware, namely, rollers, rails, cables, carriers, pins, locks, clips, brackets and screws; pipes and tubes of metal; doors, gates, windows, window frames and window coverings of metal