1. The distinguishing sign shall be composed of one to three letters in capital Latin characters. The letters shall have a minimum height of 80 mm (3.1 in.) and their strokes a width of 10 mm (0.4 in.) The letters shall be painted in black on a white ground of elliptical form with the major axis horizontal.

2. If the distinguishing sign is composed of three letters, the dimensions of she ellipse shall be at least 240 mm (9.4 in.) in width and 145 mm (5.7 in.) in height The dimensions may be reduced to 175 mm (6.9 in.) in width and 215 mm (4.5 in.) in height if the sign carries less than three letters.
As regards the distinguishing signs for motorcycles, the dimensions of the ellipse, whether the sign is composed of one, two or three letters, may be reduced to 175 mm (6.9 in.) in width and 115 mm (4.5 in.) in height.

3. The distinctive letters for the differen States and territories are as follows:

Any State which has not already done so shall on signature or ratification of, or accession to, this Convention, notify the Secretary- General of the distinctive letters selected by that State.

4. When the distinguishing sign is carried on a special plate this plate shall be fixed in a vertical or nearly vertical position and in a plane perpendicular to the longitudinal axis of the vehicle itself. When the sign is fixed to or painted on the vehicle itself, this shall be done on a vertical or nearly vertical surface at the back of the vehicle.