This subpart sets forth the procedures and regulations for implementation of Article 1904 of the North American Free Trade Agreement under the Tariff Act of 1930, as amended by title IV of the North American Free Trade Agreement Implementation Act (19 U.S.C. 1516a and 1677f). These regulations are authorized by section 402(g) of the North American Free Trade Agreement Implementation Act and 19 U.S.C. 1335.