Biohazard Caution Tin Metal Steel Sign, Biological Hazard Symbol, Rusted Design :: 11.5 x 17.5 inches [AYY033] 11.5 x 17.5 inches Made in the USA using sturdy 24 gauge STEEL, not easily bent. Holes for easy hanging are reinforced with metal grommets. Edges are rolled and hemmed for safe handling.