Set of variations on a clip to hold 5mm corflute (sign) plastic board. They are intended to be held in place using double sided tape.

The bottom clips are closed so that the board cannot fall through.

I use these to hold a sheet to the front of my DYI enclosure.

The STL files are correctly oriented, print as is with your favourite settings and filament. I would suggest 3 perimeters and whatever layer height you like (I used 0.3mm with a 0.6mm nozzle). No supports are required.