6 Common metals and alloys of common metals; metallic building materials, not including cornices or mouldings; precoated metal sheet, coil and strip; precoated metal building materials, not including cornices or mouldings; prepainted metal sheet, coil and strip; prepainted metal building materials, not including cornices or mouldings; metal in the form of sheets, coils, strips, plates, bars, rods, slabs and ingots; metal roof and wall cladding, ceiling battens, trusses, purlins, structural decking, metal formwork and reinforcing materials for buildings