Off-interstate route sign (1 or 2 digits)
Mutcd Code: M1-2 (1 or 2 digits)
The Manual on Uniform Traffic Control Devices (MUTCD) is a document issued by the Federal Highway Administration (FHWA) of the United States Department of Transportation (USDOT) to specify the standards by which traffic signs, road surface markings, and signals are designed, installed, and used.
