I'm not sure but I think this is a gadget and I'm sure it's from the 50s or 60s. It's sheer and about 1-1/2" tall, circular and the mold # is 357. It's very unusual in that the bottom, or I'm assuming the bottom, is open and has teeth-like appendages and a plastic screw in the center that runs up the center of this little item, almost as if to anchor it something.
I hope my description isn't too obscure. Thanks for any help.