I had three glass beds laying around from Ender 3s that have been upgraded to flex plates, and wanted to use them as shelves for models and such. 

So far I've printed this in both PLA and PETG, both have held up well, at least for the lego and resin models i've been putting on them

The included Mk4 print file is sliced with Prusament PETG profile, 6 walls, 30% adaptive cubic infill- it should be more than strong enough for whatever is set on it.

Included the step and Fusion files to make it easier to adjust for whatever you need.