2. Choose Size Next, pick the size of sign you'd like - we can create street signs ranging in size from 24" x 6" up to 48" x 9". Keep in mind that both the size of your text and the number of characters is proportionate to the size of your sign. ...
Link: https://mutcd.fhwa.dot.gov/htm/2009/part2/part2l.htm#section2L02_para07 LED Digit Size The MUTCD gives specific requirements for the radar speed feedback sign letter height. Section 2L.04.06 Guidance: Except as provided in Paragraph 18, word messages on changeable message signs shoul...