I actually have a set of these pliers somewhere out in the garage. I never knew what it was. They are belting pliers. They punch a hole in teh end of a belt so you can connect the ends of the belt together with a metal clip.
Well...It looks like Tom got it right first. I would never have guessed what that tool was for. The question for BlueRiver...Does Tom get a reward? Maybe a nipple or two...oh never mind...