A simple desk hygrometer holder that recalls the Pirelli Formula 1 tyre, the hygrometer I used can be found on Amazon in 3 pieces., it works well and is cheap.
https://www.amazon.it/dp/B09DKPN9GY?psc=1&ref=ppx_yo2ov_dt_b_product_details.
in the files you will also find the clean step without any logo !