0 7306.50 Tubes, pipes and hollow profiles, welded, having a circular cross-section, of alloy steel other than stainless (excl. seamless, tubes and pipes having internal and external circular cross-sections and an external diameter of > 406,4 mm, and line pipe of a used for oil or gas pipelines or casing and tubing of a kind used in drilling for oil or gas) 5 5 4 4 3