7306.30.50.57 - With an outside diameter exceeding 50.8 mm but not exceeding 114.3 mm

This HTS classification covers welded tubes, pipes, and hollow profiles of iron or non-alloy steel with a circular cross-section. Specifically, it includes items that have a wall thickness of 1.65 mm or more, are not of the "Other" designation at the preceding level, and possess an outside diameter that strictly exceeds 50.8 mm but does not surpass 114.3 mm. These are essentially medium-sized circular steel pipes or tubes that meet the detailed dimensional and welding criteria of the preceding subheadings.

This category is distinguished from its sibling, 7306.30.50.56, by the specified range of the outside diameter. While this category is for diameters *exceeding* 50.8 mm but *not exceeding* 114.3 mm, the sibling category (7306.30.50.56) exclusively covers those with an outside diameter *not exceeding* 50.8 mm. Therefore, the key differentiator is the upper limit of the diameter for the smaller tubes and the lower limit for the tubes classified here.

As this is a leaf node, there are no further subcategories to introduce. Classification decisions for items falling under 7306.30.50.57 will therefore be definitive at this level, based on the precise physical characteristics of outside diameter within the defined range and the fulfillment of all preceding technical specifications for welded, circular cross-section, iron or non-alloy steel tubes.