Those are part of the museum display. I can't find exact dimensions but from the descriptions given, I would say its around 3 inches folded. the handles on the folding types were made from metal, wood, and bone, and the blades have been made from pretty much everything that can hold an edge.
I really want to guess this one right so I can post a picture. Normally I'd post a shoe string or a light bulb b/c I have no idea where to find these things that y'all come up with, but I have one in mind now.
