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.

Amends the Buy American Act to define unreasonable cost of American made goods as greater than the sum of the lowest bid to offer foreign made goods plus 50 percent thereof. States that goods shall not be deemed to have been mined, produced, or manufactured in the United States unless the cost of the components in such goods mined, produced, or manufactured in the United States constitute 75 percent of the total cost of the components of such goods.

States that any law enacted by any State or political subdivision of a State requiring preference to be given to American-made goods for public use shall constitute a valid State act which in no way encroaches upon the power of the United States to regulate foreign commerce.