Section 15 BASE METALS AND ARTICLES OF BASE METAL 73 ARTICLES OF IRON OR STEEL 73 06 OTHER TUBES, PIPES AND HOLLOW PROFILES (FOR EXAMPLE, OPEN SEAM OR WELDED, 73 06 61 TUBES/PIPES/.., OF SQUARE/RECTANGULAR CROSS-SECTION, WELDED, OF IRON/STEEL Commodity Code Description 73 06 61 00 TUBES/PIPES/.., OF SQUARE/RECTANGULAR CROSS-SECTION, WELDED, OF IRON/STEEL