this thread is great. I'm trying -- and failing -- to imagine what Walter Bonatti used back in the day.
I started climbing in 1994 (20 years ago!? wow.) Even back then the only device I saw at the crags was an ATC. Never saw a Figure 8, except in a catalog, and which was immediately dismissed as a museum piece.
Steve, those pictures ore of a prototype "square tuber" that I was working on with Greg Lowe in mid-1991. I left Lowe in December 1991 to start Trango and the people remaining at Lowe abandoned the project so I took it on at Trango where it was refined and became the Pyramid.
Bonatti, at his time, was known for using equipment from earlier times. He probably used a set-up of carabiners for self-belay. I have never been able to see any special belay devices among his equipment on photos.
Klaus, what's with the bottle opener, or whatever that is? I must have
three Sticht plates, a double-niner, a nine/eleven, and a double-eleven
but I've never seen that sheet metal thingy. It looks after market.