All traffic-control signs, signals, and devices shall conform to the manual and specifications approved by the state highway commission of Montana. All signs and signals required hereunder for a particular purpose shall so far as practicable be uniform as to type and location throughout the city. All traffic-control devices so erected and not inconsistent with the provisions of state law or this title shall be official traffic-control devices. (Ord. 210 § 39, 1957)