Wolfgang wrote:
...The
jaws might be used where smaller parts needed to be clamped
together....say, where two straps crossed or something like that.

A couple of other possibilities come to mind. The jaws might not be
meant to hold anything at all. They may actually be calipers whose
function is to set the proper spacing between the "gears," assuming the
latter to be adjustable. This doesn't look likely based on what's
visible in the photo but.....

The jaws could also be meant to clamp onto some stationary
object....say, a work bench. The material being worked on could then
be ratcheted through the device for stretching or holding taught which
would, in essence, make the thing a mini-winch of sorts.

Wolfgang