6
Castings, foils, powder and rolled, drawn or extruded semi-finished articles of common metals and their alloys; metal tubes; plastic coated metal conduit, namely, thermally insulated tubes made of copper or copper alloys; metal pipe couplings and joints
11
Plastic coated tubes and piping for heating, ventilating, cooling, drinking water and sanitary installations, namely, tubes and pipes being parts of heating systems composed primarily of tubes, pipes and pre-assembled manifolds through which cold or low temperature water circulates; pipes being parts of sanitary facilities
17
Synthetic insulating tubes and formed parts of synthetic material for covering installation pipes, namely, insulation jackets for industrial heating pipes; pipe insulation for plumbing tubes; synthetic material insulators for connection and branching of isolated pipes, namely, for insulated pipe supports, insulation jackets for industrial pipes, pipe insulation for plumbing tubes; pipe jointing parts of plastic, namely, joint packing for insulated heating and plumbing pipes