2.137″ high x 1.602″ wide x .628″ deep. Steel body. Brass shackle. Keyway: Flat. “YALE & TOWNE MFG. CO.” is embossed on the obverse of the shackle. “PATENTED JAN.7.90” is stamped on the obverse of the shackle. “STAMFORD, CONN. U.S.A.” is embossed on the reverse of the shackle. “PAT JAN 7, 1890 NOV 19, 1901” is stamped on the base of the body.Patent # 418884 Waldo R. Ballou Patent # 686882. (PK-MS-012P-S2P).