7307.19.90.30 - Unions

This classification, 7307.19.90.30, specifically covers "Unions" made of iron or steel that are used as tube or pipe fittings. Unions are characterized by their ability to join two pipes or tubes together, often with a threaded connection, and can be disassembled without cutting or damaging the pipework. These fittings are distinct from other categories within Section XV and Chapter 73 due to their specific function as a detachable coupling for fluid or gas conveyance systems, and their manufacturing process which, in this instance, is not covered by the preceding "cast fittings" or "other" sub-classifications at higher levels.

As a leaf node, 7307.19.90.30 does not have further subdivisions. Therefore, the focus for classification purposes is on ensuring that the union fits the description of being an iron or steel pipe fitting and is not otherwise specifically classified under a more granular HTS heading. This category serves as the final destination for unions that are not cast iron fittings and are not categorized under any other preceding "other" sub-classifications within the 7307 heading, making it the residual category for non-cast iron unions.