This is a Solar Radiation Shield aka. Stevenson Screen for Air Temperature and Humidity Measurement. It's inspired by micromet's shield but I redesigned it from scratch. It should be compatible with sensor mounting adapters for their shield but bette check yourself if you are going to use one of them.
All files are also available on GitHub and pull requests for improvements or issue reports are welcome.
I plan to make this thing customizable in the future, just have to figure out the details.
I highly recommend you use a UV resistant filament AND to apply a UV resistent coating on the finished part.
I printed the parts using a black PLA filament from (Extrudr)[https://www.extrudr.com/] and then spray painted the whole part with a clear plastic base coat, then spray painted the outside white, before spray painting the whole part with a protective clear coating. That way I achieved the maximum amount of opaqueness, a minimum of reflections to the inside, while maintaining high reflectivity on the outside for a minimum dissipation of solar radiation by the shield itself.