I needed a case for an RPi based Environmental Sensor with the added requirement of wired ethernet, so I designed this case with these components in mind:

• Raspberry Pi Zero variant,
• UCTRONICS Power Adapter (specifically this one),
• (opt.) a 30x30 fan (like this one) and
• a sensor outside the case wired through one of the holes (add cable ties for strain relief).

The ethernet adapter should clip right into place, but maybe add some double-sided tape or something. The holes for mounting the lid are designed for M4 threaded inserts (specifically these). The Pi itself can be mounted as well (optional) using M2.5 screws and threaded inserts (these). Also the case has mounting holes for either a cable tie or an M5 screw.

This should print without supports (bridge looked okay for me at least), but you can use painted in supports along that edge. I printed with ABS, but PLA should be fine as well.