This is meant to be used with the stereotypical Game screen that you can buy from wizards of the coast. Mine came from the Lost Mine to Phalandever box. It's basically a shelf/holder that can hold whatever you want. It's also super modifiable pretty easily in whatever application you want. You can make it wider to hold phones, smaller to hold just one mini, whatever. I use it because there are parts of my screen's text that I never use so I don't mind covering it up in exchange for helping clean out my clutter.

The File I uploaded is 90mm x 60mm (LxW) with a 5.5mm thick.

One thing I forgot to mention, for better printing and so you don't need supports, lay it on it's side.