54.16—Marking of products.
All products for which class and grade under the standards are determined under the regulations, or the immediate and shipping containers thereof, shall be stamped, branded, or otherwise marked with an appropriate official identification: Provided, That except as otherwise directed by the Chief, such marking will not be required when an applicant only desires official certificates. The marking of products, or their containers, as required by this section shall be done by official graders or under their immediate supervision.