6
Common metals and their alloys; metal building materials; transportable buildings of metal; materials of metal for railway tracks; non-electric cables and wires of common metal; ironmongery, small items of metal hardware; pipes and tubes of metal; safes; goods of common metal not included in other classes; ores.
gauge and thief holes for oil tanks, vacuum and pressure relief valves for oil tanks, oil still safety valves, flame-arrester casings, flame snuffers, oil-tank fittings, pipe fittings, [ couplings, t's, elbows, headers, oil-pipe-line lock boxes, oil pipe-line filter coulmns, ] oil-tank free vents, flame-arrester units, double-acting pressure and vacuum control valve, oil-storage conservation system, vapor-control system, man-hole covers for oil tanks, [ double-flange pipe collars for oil tanks ]