Love the people smarter than me. Have a drill I found in the dirt at a repo cleanout, wiped it and blew out the case- didn't disassemble. Fired it up and got knocked on the maximus gluttumus. Plug was 2 prong, figured I'd put a 3 wire on it but in the handle it was 3 wire!, changed plug to 3 prong, works well (just a little bite if you are wet- GFI doesn't always catch it). Now I wonder what kind it is. Chuck is 1/2" and labeled SUPERIOR.  Has fwd and rev switch, runs slow and has much wrist busting power. Prepaid thanks to all commentators.  Joe

Does it have two little oil holes on the front of the gear reduction case. they would have screws in them. if so it could be thor or ingersal rand   bob w.

Thanks, I checked- no screws on drive head only the 4 that hold it to the body of the drill

Cummins?

It is a SHOPMATE by Portable Electric Tools [PET] of Chicago.  Virtually identical drills were sold as DAYTON, with a blue name band, and as MURPHY, with a black band.  PET apparently moved to Geneva, Ill; the later products have a ZIP code of 60134, but earlier ones have the city postal code (Chicago 20, Ill., in this case).

Thank you SIR. I am in awe. At least I know what it is other than a wrist bender that I can't do with out.

Found yet another version of this drill during the weekend.  No, I didn't buy it at $35, in part because it was with another electric Keen Kutter tool (belt sander, I think it was), and I thought it made more sense for some Keen Kutter Kollector to Keep them Klose together.  The vendor had quite an array of hatchets and other Keen Kutter tools, mostly in very nice condition.  He also had quite a few Winchester tools, and several other very collectible brands.  This was at Baraboo, Wisconsin, at the Badger Steam & Gas Engine swap meet.

Oh, what a tangled web . . .
I just found a black-banded version with G.W. Murphy prominently printed at the back, but both sides are illegible due to scratching.  At the front, beneath the chuck, there's a stick-on label that says "SHOPMATE".  And here I had thought that all with black labels were the G. W. Murphy version!  Carries same model number (520) as a Shopmate version I have.