7304.39.00.04 - Having an outside diameter of 38.1 mm or more but less than 190.5 mm

This HTS classification, 7304.39.00.04, pertains to seamless tubes and pipes of iron or nonalloy steel, specifically those of a circular cross-section. The defining characteristic for this category is the outside diameter of the tubing. It encompasses products where the outside diameter is equal to or greater than 38.1 millimeters but strictly less than 190.5 millimeters. These tubes and pipes are intended for use in various heat transfer applications, including boilers, superheaters, heat exchangers, condensers, refining furnaces, and feedwater heaters.

This specific category can be distinguished from its siblings by its precise diameter range. For instance, 7304.39.00.02 covers similar seamless tubes but with an outside diameter smaller than 38.1 mm. Conversely, 7304.39.00.06 and 7304.39.00.08 classify tubes with larger outside diameters, starting at 190.5 mm and exceeding 285.8 mm respectively. Therefore, the critical differentiator for 7304.39.00.04 is its intermediate diameter range.

As this is a leaf node within the HTS, there are no further subcategories. Classification at this level is determined solely by the material composition (iron or nonalloy steel), construction (seamless), cross-sectional shape (circular), intended use (heat transfer applications), and, most importantly, the specific outside diameter range specified. Importers and exporters must ensure accurate measurement of the outside diameter to correctly assign goods to this classification.