To amend the National Highway System Designation Act of 1995 to prohibit the Secretary of Transportation from requiring States to use the metric system with respect to designing, advertising, or preparing documents for Federal-aid highway projects.

Amends the National Highway System Designation Act of 1995 to make permanent the prohibition against the Secretary of Transportation requiring that any State use or plan to use the metric system in designing or advertising, or preparing plans, specifications, estimates, or other documents for, a Federal-aid highway project eligible for assistance under Federal highway provisions.