This is a simple pegboard mount for my handheld digital anemometer.

This model is sold under multiple brands and is available for about $16 on Amazon.

The model is designed parametrically in Fusion 360, so you can make a similar but differently dimensioned part very easily. You can download the Fusion 360 file here.

I also have a post on my website discussing the design.

See how it fits here:

These parts are printed with Prusament Galaxy Black PLA.

Here is my Thermometer Mount too.

The peg design is from Make Anything, as shown in this video.