very unique and all original american machine age "edge glow" illuminated interior commercial building lobby elevator informational sign designed and fabricated by robinson & co., t.l., chicago, ill. the double-sided hanging sign contains two thick plate glass panels with rounded edges and lightly edges lettering. the art deco style edge-lit sign is equipped with a metal housing that contains two opposed incandescent light bulb sockets for illuminating the panels with lettering. when lit, the informational sign emits a warm glow against a sea green background sandwiched between the thick glass plates. the bent steel tabs (found along the bottom) prevent the panels from falling away from the socket housing. measures approximately 14 1/2 x 2 1/4 x 9 1/2 inches.