single vintage american industrial stamped steel oversized metal sign fabricated by or for the street & sanitation department, chicago, ills. the sign was originally used as a city street traffic sign, but at some point it was repurposed into a makeshift "maintenance dept. only" hours of operation sign used in a city department building. the signs contains bolt silver metallic lettering against a weathered and worn black enameled background. measures 24 x 24 inches.