Any ideas on this? The "jaws" have serrations, and there is "NEWXXX" on the lower jaw of the larger end (X's aren't readable yet, and I'm not sure how many letters there are total). Center hole looks to be threaded, and there looks to be a "line" punched into the surface on both sides that bisects each of the holes. You can barely see it on the top hole in the pic. It's been soaking in vinegar for the last 24hrs and is about free time of rust at this point. Found it this past weekend as were cleaning out the garage at the farm. Grandfather was born in 1919, grew up on a farm, went to war in 1941, then came home and farmed/ranched the rest of his life. I've restored a lot of his old tools over the last couple of years, but just ran across this one.