A bill to amend title III of the act of March 3, 1933, commonly referred to as the "Buy American Act", with respect to determining when the cost of certain articles, materials, or supplies is unreasonable; to define when articles, materials, and supplies have been mined, produced, or manufactured in the United States; to make clear the right of any State to give preference to domestically produced goods in purchasing for public use, and for other purposes.

Provides that the head of a Federal department or independent establishment shall not deem unreasonable any bid or offer to furnish manufactured or unmanufactured aritices, materials, or supplies mined, produced, or manufactured in the United States if such bid or offer does not exceed an amount equal to the sum of the lowest bid or offer to furnish such articles, materials, or supplies not mined, produced, or manufactured in the United States, plus 50 percent thereof, and that an article shall be deemed to have been mined, produced, or manufactured in the United States only when the cost of the components mined, produced, or manufactured in the United States exceeds 75 percent of the cost of all components incorporated in the article.

Provides that any law, regulation, or ordiance enacted by any State, or political subdivision thereof, which provides that preference be given to the acquisition of articles, materials, and supplies of United States manufacture for public use by that State, or any political subdivision thereof, shall constitute a valid exercise of the State's or political subdivision's, police power and shall not constitute an encroachment or infringement upon the power of the United States to regulate foreign commerce or to conduct foreign affairs. (Amends 41 U.S.C. 10a 10d)