Well, I used to have one, but do not remember what it was for. I am pretty sure it was an "extra" from a tupperware party. I am 79, and my memory bank is a bit "used up". How about putting your fingers in the "grooves", your thumb in the round hole and painting your nails? Or, like one of you said, maybe it is a foot for a lame duck.
If anyone knows, please tell us.