It is hard to find a good case for Orange Pi PC, so decided to make my own :)
This one is very tightly designed and features opening for all ports, including the GPIO and 3 serial port pins.
All done in OpenSCAD.
Technical
Four M3 screws, about 15mm long (or longer as needed).
Print from any material. For me ABS works best.
Recommended quality is 0.1mm.