In a race, each horse shall carry a conspicuous saddle cloth number, corresponding with its number on the official program. Each horse making up an entry shall carry the same number, with distinguishing letter; for example, 1, 1A; 2, 2X and so forth. In the case of a mutuel field, horses comprising the field shall carry an individual number; for example, 12, 13, 14 and so on.
N.J. Admin. Code § 13:70-10.3