These are recommended by Police, Fire and Emergency officials. This is a 911 reflective grade sign, same as used by the D.O.T. on interstate and roadway signs. They are very highly visible in the daytime and nighttime. The base material is (1/16") 6061 aircraft grade aluminum, not steel. Sign measures 6" x 18" Vinyl: Engineer Grade 7 year white outdoor durable reflective vinyl with BOTH sides. Meets the federal specification requirements. MOUNTING BRACKETS ARE NOT INCLUDED. The more numbers in this area, the smaller each number will be. The height of each number will vary from 2" tall numbers (using 5 numbers on the sign) to 4" tall numbers (3 numbers on the sign) ****Mounting brackets sold separately**** Custom orders are NON REFUNDABLE. Please make sure you fill in the fields correctly before submitting your order. Check out our Facebook page (Granite City Graphics LLC) and see photos of recent projects for ideas!