N.C. Gen. Stat. § 20-190

The Department of Public Safety shall adopt some distinguishing uniform for the members of said State Highway Patrol, and furnish each member of the Patrol with an adequate number of said uniforms and each member of said Patrol force when on duty shall be dressed in said uniform. The Department of Public Safety shall likewise furnish each member of the Patrol with a suitable motor vehicle, and necessary arms, and provide for all reasonable expense incurred by said Patrol while on duty, provided, that not less than eighty-three percent (83%) of the number of motor vehicles operated on the highways of the State by members of the State Highway Patrol shall be painted a uniform color of black and silver.