SIGN KEEP BACK 100FT 18X18 .080 ALUM B/O DG W20-V10. The aluminum truck safety sign conveys your transport message in written form. Made of tough aluminum coated in an 18 x 18 inch enamel print. Its rounded corners are 0.20 inches and have mounting holes for easy installation. Ideal for use indoors or outdoors. Plus, it resists ultraviolet rays, chemicals, abrasion and moisture for long life.