7304.59.80.55 - Having a wall thickness of 19 mm or more

This HTS classification, 7304.59.80.55, pertains to seamless tubes, pipes, and hollow profiles made from iron or steel, specifically of other alloy steel, and having a circular cross-section. This particular subheading is designated for such articles where the wall thickness is 19 mm or greater. These are generally heavy-duty pipes or tubes intended for specialized industrial applications where structural integrity and resistance to high pressures or extreme conditions are paramount.

This category is distinguished from its siblings by its specific wall thickness criteria. HTS code 7304.59.80.45 covers similar seamless alloy steel tubes with wall thicknesses less than 12.7 mm, while 7304.59.80.50 includes those with wall thicknesses ranging from 12.7 mm up to, but not including, 19 mm. Therefore, 7304.59.80.55 exclusively captures those with a substantial wall thickness of 19 mm or more, signifying a robust construction.

As this is a leaf node within the HTS structure, there are no further subcategories. The classification is solely determined by the material (other alloy steel), shape (circular cross-section), construction (seamless), and the specific wall thickness of 19 mm or more, within the defined outside diameter range of 190.5 mm to 285.8 mm. This precise combination of characteristics ensures that only the heaviest and most robust seamless alloy steel pipes and tubes fall under this designation.