Both the SOI & KAC were small booklets, the size of a small manual, never bound but were put together in the TOC by S-3, so it could be destroyed if needed, never standardized. Each day in the book had a certain number to coincide with the day of the week and the time. To enter the net, you had to authenticate to enter the net and be able to communicate with the secure freqs.

They were ALWAYS carried by the 1-0, usually in a plastic bag, connected to dummy cord and worn around the neck and tucked into a shirt pocket!

Thanks to Paul W Miraldi for the information and the reference photos, I am making my own reproductions of these books, I even found the same brand "prong" fasteners as used in the 60's.