7304.11.00.80 - Having an outside diameter exceeding 406.4 mm

This HTS category, 7304.11.00.80, specifically covers seamless tubes and pipes made of iron or steel, designed for use as "line pipe" in oil or gas pipelines. The defining characteristic of this classification is its large diameter, requiring an outside diameter that *exceeds 406.4 mm*. These are robust pipes intended for the transport of oil and gas over significant distances, typically under high pressure.

Distinguishing this category from its siblings is crucial for accurate classification. Unlike sibling categories 7304.11.00.20 and 7304.11.00.50, which cover smaller diameter line pipes (not exceeding 114.3 mm and exceeding 114.3 mm but not exceeding 406.4 mm respectively), this node is reserved for the largest caliber line pipes. The substantial diameter difference signifies variations in manufacturing processes, potential applications, and handling requirements, necessitating separate tariff treatment.

As this is a leaf node within the HTS structure, there are no further subcategories to introduce. The classification is precise and based solely on the material (stainless steel), application (line pipe for oil or gas), construction (seamless), and the specific outside diameter exceeding 406.4 mm. Proper measurement of the outside diameter is the primary determining factor for classifying goods under this specific code.