Section 15 Base metals and articles of base metal 73 Articles of iron or steel 73 07 Tube or pipe fittings(eg.couplings,...),of iron or steel 73 07 23 Butt welding fittings 73 07 23 00 Butt welding fittings Commodity Code Description 73 07 23 00 000 Butt welding fittings
