It's a platter mat. It goes between the record and turntable and is supposed to make it sound better, for various reasons. https://www.gearpatrol.com/audio/best-platter-mats-for-turntable/
edit literally as soon as I hit post I realized this was wrong. I think it's actually a sanding disk (not sure of proper name)
Yeah there would need to be a hole in the center for the post in the center of the turntable if it were a record mat.
Fun fact: sometimes a record mat makes it sound worse, it totally depends on the record player.
Yes this is in fact a shitpost and that is in fact a 17" 60 grit floor sanding mesh.
The vinyl for Earth 2: Special Low Frequency Version looked pretty close to that lmao