3 1/4″ high x 2 1/4″ wide x 3/4″ deep. Steel and Brass body. Steel shackle. The Eagle catalog states that this lock was made for the United States Government and that it was waterproof. This lock is #2 of 4 prototypes each with some variation. This lock was never put into production. Make note of the unfinished rivets on the reverse of the body. Designed by: Frank W. Mix.