hard to find and highly collectible late 1930's american industrial brightly colored porcelain enameled factory cautionary sign possibly fabricated by the stonehouse steel sign co., denver, co. the single-sided wall mount safety first sign is comprised of heavy gauge die cut steel with vitreous enamel finish. contains surface wear in the form of minor porcelain loss around the grommets, surface discoloration and paint splatter. the edges are equipped with six screw holes for mounting purposes. salvaged from a michigan automotive assembly plant. measures 20 x 14 inches.