The author remixed this model.
I rounded off the corners and made the top screen frame even as I liked it better.
The backplate is unchanged and can be re-used if you already have it.
Pictures are from a specimen printed with extrudr BioFusion Metallic Grey filament.
As a wall mount you can e.g. epoxy-glue this to the back:
https://www.printables.com/de/model/176540-simple-wall-mount