American Saw was one of the early alligator wrench makers, and they held the patent on this one. Patented in 1875. They sold the alligator wrench business to J.A. Roebling of Brooklyn Bridge fame. This wrench was given to me by one of the members of my Tool Talk Forum.

American Saw #1 Alligator wrench by Noel C. Hankamer, on Flickr

Stupid question I have wanted to ask, how does the wrench work, it would seem to me that it would tear up a nut that was not loose, also because they appear usually thinner than than most nuts it seems to me they would wear a pattern in the nut or bolt again eventually destroying it, also I notice alot of them are open in the center, take this one for example, was this just a weight saving gimmick AKA a steel saving deal

These were used on the old square fasteners and pipe and tubing. they were an improvement on pipe tongs of course, but yes, they will tear up a fastener. The holes in the handle were often sized for the same square nuts and bolts of those days. Quite a few of the smaller adjustables were not much thicker, and were made of stamped steel, so they weren't much better,

They will tear up fastners.........Thats what I thought, thanks