Alert people to additional parking with this sign manufactured from RA Type I Engineer Grade Prismatic Reflective Sheeting on .080 Aluminum. This material will reflect at night when light hits it. Signs are .080 in. thick with a Type I engineer grade prismatic reflective sheeting applied over the surface. Signs will never rust and have an average lifespan of 7 years. Signs meet most State and Federal D.O.T. specifications. Measures 12 in. x 18 in.