The metric system of measurement shall be defined as the International System of Units as established in 1960, and subsequently maintained, by the General Conference of Weights and Measures, and as interpreted or modified for the United States by the Secretary of Commerce.
15 U.S. Code § 205 - Metric system defined
R.S. § 3570 derived from act July 28, 1866, ch. 301, § 2, 14 Stat. 339, 340.
2007—Pub. L. 110–69 amended section generally. Prior to amendment, section read as follows: “The tables in the schedule annexed shall be recognized in the construction of contracts and in all legal proceedings as establishing, in terms of the weights and measures on June 22, 1874, in use in the United States, the equivalents of the weights and measures expressed therein in terms of the metric system; and the tables may lawfully be used for computing, determining, and expressing in customary weights and measures the weights and measures of the metric system.”