46 CFR 131.865: Inflatable liferafts and inflatable buoyant apparatus.

The number of the inflatable liferaft or inflatable buoyant apparatus and the number of persons it is approved for must be marked or painted, in a conspicuous place in the immediate vicinity of each raft and each apparatus, in letters and numbers at least 38 millimeters (1- 1/2 inches) high and in a color contrasting to that of the raft or apparatus. Each raft or apparatus stowed on the side of a vessel must be numbered like a liferaft in compliance with § 199.178 (c) and (d) of this chapter. No letters or numbers may go on the liferaft or on the container of the apparatus.