The 7-inch SOG knife was designed by Conrad “Ben” Baker in 1964 on behalf of a request from 5th Special Forces Group for a good quality fighting knife to be issued to operational personnel. The blue prints were submitted to several Japanese companies that provided examples to CISO. One unidentified company was awarded the contact and manufactured 1300 knives at a cost of $9.85 a piece.
Once the knives were received by CISO it was noted that there was an issue with the blades design. The knifes ricasso feed directly into the cross guard and could not be easily withdrawn when they were stuck into pig carcasses. The knives were returned to the manufacture and a finger grove was ground into the blade before they were reassembled. It should be noted that on an original wartime 7-inch SOG knife there is a small void on the bottom of the cross guard where the blade was reshaped.
The Japan Sword Company copied the design with a shorter blade and sold the knives on the civilian market through advertisements in military and men’s magazine. These knives are period but were not an authorized CISO product.