A simple frame sized to house one or more sheets of A4 paper.

Bornt as a simple way to keep the grubby hands of costumers away from things, came out pretty useful as dm screen to keep tables, notes and npc sheets on the inside and maps for the players and other stuff on the outside.

Alternate frame A and frame B to make it foldable, from two to as many as you need. Use long screws between frames plus one long and one short at the ends of the chain (the picture with the open screen migh be clearer than my explanation)

I printed it with 2 shells and 5% infill and so far everything is good, probabily 3 shells would make the little T that join the two halves of every frame a bit sturdier (make sure to clean those well before pushing)

Edit: i added a little washer for the hinges if you feel too much play opening and closing