7307: Pipe fittings, of iron or steel

730711: Pipe fittings of non-malleable cast iron 730719: Pipe fittings of malleable iron or steel, cast 730721: Flanges, stainless steel 730722: Threaded elbows, bends and sleeves of stainless steel 730723: Pipe fittings, butt welding of stainless steel 730729: Pipe fittings of stainless steel except butt welding 730791: Pipe flanges, iron or steel except stainless/cast 730792: Threaded fittings, iron or steel except stainless/cas 730793: Butt weld fittings, iron/steel except stainless/cast 730799: Fittings, pipe or tube, iron or steel, nes 7307: Pipe fittings, of iron or steel