46 C.F.R. § 161.012-15 – Markings.

(a) Each light manufactured under Coast Guard approval must be permanently and legibly marked with:
1. (1) The manufacturer's name or trade mark that clearly identifies the model designation;
2. (2) The Coast Guard approval number assigned to light; and
3. (3) Instructions on how to activate the light.
(b) The power source of each light must be permanently and legibly marked with its date of manufacture and expiration date. Each date must include the month and year.