Hello, When I picked this up, I wasn't paying much attention to it. Looked like a saw set at first glance. The plunger & anvil are flat, 1/2" diameter, and the anvil adjusts from 0 to 5/16" (with handles closed). In raised lettering inside one handle COLUMBUS O X X. Looks like more lettering on the other handle, but loaded with paint? japanning? not sure of the finish. Looks like it would flatten a saw tooth, rather than set it, plier type saw wrest? Other guesses are reloading tool? Crimper? Regards, Lou