c. 1950's american vintage industrial single-sided safety first interior wall-mount factory sign salvaged from a recently shuttered chicago tool & die machine shop. the lightweight cautionary sign is comprised of thin sheet steel with baked enameled finish. the sign contains pre-drilled holes in corner for mounting purposes. general wear and minor surface discoloration evident. two matching signs available. manufactured by stonehouse signs inc., denver, co. measures 10 x 7 inches.