Case for Zigstar Olizig PoE zigbee coordinator/router. Insert Olizig into case, antena port first, then gently push ethernet connector down and screw on the antenna from the outside. Finally close the lid with a little force.

If your Olimex is slightly larger or your printer has different tolerances, you can open the Fusion360 files and change the parameters.

Print with a brim and good first layer calibration, to prevent the case from lifting off the print plate.