911 Blue Reflective Address w/ 3" Numbers Mailbox Marker Home Business Vertical Mg2 Signs Reflective material to make it easier to find at night. Same material used on highway signs. Industrial grade aluminum for durability and long life. Never worry about rusting or breaking again. Holes in the corner making it very easy to mount on top, on the bottom or even on the side. We will make the numbers on your sign your mailing address unless contacted by customer with different instructions Same material used on highway signs.