The GL-M2 5G Development Board from GL-iNet doesn't come with a case. It is meant to be a development board. They did not create an official case, and I wanted to protect my Modem.
The top and bottom pieces fit together without any screws being needed. The antennas of the GL-M2 help secure the board in place without screws. Test prints on Prusa Mini.
Edit: I added air vents along the side and along the top of the case to help with heat ventilation.
The author marked this model as their own original creation.