This is a replacement decorative bulb cover for a ceiling fan light fixture. The base diameter measures about 53 mm. I used the the base measurements from the fixture that I have in my living room. It is a generic fixture so I can't say what brand it is. It has three thumbscrews that tighten down on the shade when you insert the base into the fixture.
There are currently 2 designs here, one has the design cut completely through and the 2nd is partially through. I will be adding different designs to this in the near future.
I would not recommend these for use with incandescent bulbs or any bulbs that get real hot.
Sliced with Simplify3D
Original Post 7/23/2019