These pliers don't close all the way, and the unequal jaw width and nubs on the ends make me think there's some other part missing. Curiously no other marks, and it looks like it was chrome plated long ago. If this was a modern tool I'd say it's missing the steel loop for removing spin-on oil filters, it has that look to it (just 50ish years too old for that).

A couple of things come to mind, snap ring pliar and a piston ring compressor which is similar to the oil filter wrench except  there are several sleeves with the piston ring compresser.

Hello, Guys . You are both on the right track.Try this link, I believe it may help.         http://www.datamp.org/patents/advance.php?inc=1#  Regards,Lou

jar opener!
http://www.datamp.org/patents/displayPatent.php?pn=693353&id=15806

That's funny as all get out.  I knew that tool looked familiar but couldn't place it. 
I had a complete one a couple years ago and sold it to a fellow.  He thought it was for inserting pistons into the block of a small engine.  It made sense to me---at the time.

That's a pretty neat one MPT. Any chance you might find the missing ring/loop?

I dug through every box and looked under every table at the yard sale where I picked this thing up and couldn't find any other parts.  But now I know what it is and what to look for in the future. Another oddball that gets filed into the "vintage kitchenware" box.

I have had a few of those, and they are often missing the ring on the end.