“U.S. INT REV”. 3 7/8″ high x 2 1/2″ wide. Brass body. Brass shackle. A paper seal padlock. “U.S. INT REV” is stamped on the obverse of the body. “PATENT AUG.5’73” is stamped on the seal. “SLAYMAKER LANC, PA.” is stamped on the reverse of the shackle.