What format do my race numbers need to be in?

Numbers must be displayed in accordance with the specific class format; affixed in such a way to ensure their durability and legibility and be of sufficient contrast to their background. They shally be subject to the approval of Chief Timekeeper.

Any car competing at FIA and/or MSA events must display the drivers Competition number. Numbers must be a minimum 152mm (6-inches) high and 38mm (1 1/2 inches) wide. Class designation letters must be a minimum 76mm (3-inches) high and 25,4mm (1 inch) wide. Drivers competition number and class designation must be displayed in a legiable manner in a contrasting color to the vehicles background colour, or light colour on windows, in a prominent position, and must be clearly visible to the Tower personnell. Class and numbers must be in the form of permenant decals or paint. The use of shoe polish in any form is prohibited.