I got a smart meter and it's display couldn't be hung on the wall so I needed a little shelf for it.
Designed this in tinkercad.
Can be fixed to the wall with adhesive tape (I used velcro tape) or might be able to be hung on a nail or screwed through the slots.
It has a small opening to allow the wire out in case it is fitted flush to the wall.
The author hasn't provided the model origin yet.