Smartsign K-8508-AL-18x24"Warning: Falling Snow & Ice, Park at Own Risk" Aluminum Sign, 24" x 18" Heavy, 80 mil thick, rust-proof recycled aluminum Uses durable, 3M inks designed for outdoor traffic and property signs. Outlasts other sign printing. Laminate protects against abrasions, graffiti, chemicals, and weather Resists chemicals, UV rays, water, and abrasions Mounting holes allow for hassle-free installation 18"x24" has two 3/8" mounting holes, set1.5" from the top and bottom, and21" apart.1.5" corner radius