Did you notice that clamp w. two adjusters shown in the illustration to "jazzolin"-plan? It's also in the emblem of the Titebond -bottle. what is it used for, does it do anything better than a standard one?
(I picked one up assuming it was a metal working tool, but could make use of one half for a special lutherie task.)
It's simply called a screw clamp, it is an old design that still performs in the time of plastic ratchet type clamps. The screws don't have to be tightened evenly, so it will clamp odd shapes and angles.