Solo 2 Rules 3.7 VEHICLE IDENTIFICATION A. All vehicles must display numbers and class letters on both sides, which must be readable by Timing & Scoring, Course and Grid workers at all times. B. Only one set of numbers and class letters may be visible while the vehicle is running. C. Class shall be represented by the upper-case abbreviated form rather than be spelled out. Ladies' classes shall be indicated by the letter "L" following the class letters. D. Numbers and class letters should be positioned next to each other. All letters and numbers must be on body panels, not on windows. All numbers and letters must use the same typeface and the same color, and this color must provide adequate contrast to the background color. E. Numbers must be a minimum of 8" high with a 1.25" stroke. Class letters must be a minimum of 4" high with a 0.75" stroke. In all cases, the height of class letters must be between 25% and 75% of the height of the numbers. Stroke width must be at least 10% of the height. F. The "1" on two-driver cars and the "L" on Ladies' class cars are subject to all of the above requirements with regard to placement, color, size, and stroke. G. Karts may use numbers and class letters of reduced size provided that the following conditions are met: 1) Numbers must be displayed on the front and rear in addition to both sides; 2) class letters must be on both sides; 3) In no case may the numbers be smaller than 6" in height with a 3/4" stroke, using a high contrast color and background.