Hello, Does anyone recognize this wrench ? Or maybe its use ? No mfg.'s markings, small opening is 5/16"ATF , and the large opening is 7/8" ATF. Machine tool application? Thanks, Lou

The picture doesn't seem to show signs of heating, but has it been heated and bent?

I'm guessing machine tool use due to the small end.

Hello, No signs of heating, the bend is pretty  true, although the heads are not perfectly parallel, so it could have been by former owner. Papaw, the small end for a tool post set screw? Thanks, Lou

I think so