I think this one may be a manual variation of the better tool shown in the other pic for crimping the cable ferrules on to make an end loop on a cable like for a guy wire or if makin a wire choker.

Notice the raised tit at one end of the fixture and a recessed place at a 90 degree angle to that at the other end? My guess is there's a mating tit on that end that's outta sight in this view and likely a mating recessed area on the other end similarly hidden from view.

This also could be a part intended to be left in place as a clamping device once the loop is finished .... but then it wouldn'treally be a tool would it