316.16 Custom prepared products to be marked Not for Sale.
Carcasses and parts therefrom that are prepared on a custom basis under 303.1(a)(2) of this subchapter shall be marked at the time of preparation with the term Not for Sale in letters at least three-eighths inch in height, except that such products need not be so marked if in immediate containers properly labeled in accordance with the regulations in 317.16 of this subchapter. Ink used for marking such products must comply with the requirements of 316.5.