These are edges that you tape to a carboard spool so that it can run on a rolling spool holder like the one that comes with the Prusa Mini.
These fit carboard spools such as those that come from 3DQF filaments.
There are files for a full rim if you have the build plate for it or a split one that fits on the mini.
0.2mm no supports or adhesion.
The author hasn't provided the model origin yet.