J.C. (no pun intended). Haven't seen one of those in decades. Such an opener, primary use when I was young was opening juice cans. If you were desperate, without a bonafind can opener, you could also use it in repetition to open a can. Looks like I'll have to get an oldie but goodie to complete the job. Another tool in the kitchen drawer.
Speaking of cans, have noticed that many canners are making unstackable cans. Won't interlock the bottom with the top, making stacking a balancing affair. I like to keep my pantry well stocked with canned goods. Rained/snowed/iced in and so forth. When's the noise from all the newfangled stuff gonna stop. Gettin' worse, not better. Dave