This is a USAF MK. 106 practice bomb. The bomb is empty, it comes with the Brass safety clip and cloth tag that reads"TO ARM REMOVE SAFETY CLIP" Some of the printing on the side is hard to read, I will try to list it properly: BCKB PRACTICE, MK 106 MOD-I-660096955 AMERICAN ELECT, INC, CONT. NO. NIC 626(A) F.S.N. CM. It is 19 5/16" long. It has a hasp welded w a filling plug was located.