Aluminium and its alloys; Boxes of common metal; Castings, foils, powder, and rolled, drawn or extruded semi-finished articles of aluminium or its alloys; Fittings of metal for flexible pipes; Fittings of metal for rigid pipes; Metal conduit; Metal pipe couplings and joints; Metals and metal alloys; Steel in the form of sheets, plates, foils and coils; Structure joint connectors of metal