This mount is designed to attach an ESP-01 microcontroller to a krom schröder gas meter. It fits into the recess of the gas meter in which magnetic pulses can be read with a reed switch.
In my youtube-video (https://youtu.be/i9hPf0uNzFE) I explained exactly how I did it. All the files you need to build the device can be found on Github.
Remixes and improvements of my model are welcome though, you can find the FreeCAD model in the download section as well.
The author marked this model as their own original creation.