This is a wall mount for a Raspberry Pi 4 case from Canakit.

• The screw holes are designed for #6 flathead countersunk screws.
• The large cutouts are to reduce material use and (in the back) provide a bit more air flow for the case.
• There's a rounded cut out to one side to accommodate the case's ports, along with an opening to allow access to the SD card slot.

I employed my meager beginner skills to design this in FreeCAD. :-)