An advertising medium includes a frame enclosing a traffic signal control cabinet. The frame includes opposing rails for each side of the cabinet with opposing inside surfaces of the rails including grooves extending longitudinally along the rail and spaced from each other. A light panel is carried within one groove near, yet spaced from, surfaces of cabinet walls. An advertising panel is carried within a second groove. The advertising panel is spaced from the light panel and on an opposite side from the cabinet wall. A clear protective panel is carried within a third groove and opposite an outer surface of the advertising panel. Tie rods extend between lock devices which are secured to the rails such that removing the frame from its position around the cabinet is prevented. As a result, advertising material may be secured to a traffic signal control cabinet without intruding upon or modifying the cabinet.