Caution Sign SI-C-9-C-AL-03-S Aluminum .03" overall size 14."W x 10."H THIS DOOR MUST BE KEPT CLOSED, ESTA PUERTA SE DEBE MANTENER CERRADA . An aluminum constructed sign is a great choice for displaying in a variety of settings. The robust design allows the sign to be exhibited indoors and outdoors throughout harsh conditions. The aluminum fabrication will never rust, while the anti-graffiti surface coating prevents the possibility of unnecessary defacement. A .03” thickness provides stability for long lasting life.