This is a device to hold a hygrometer inside of a Sunlu FilaDryerS1 Plus. The hygrometer fits snugly into the ring area of the mount. The mount just slides into position at the very front of the dryer interior - no screws or hardware needed.

Notes:

I have used the following hygrometers:
https://www.amazon.com/gp/product/B0CMTNLK2H/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0C74T4JH1/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Both fit nice and snug. One batch did have a slight burr on the side flange so it couldn't be inserted, but the burr was easily/quickly removed with a file.

If purchasing a different model make sure it can read down to 10% as some hygrometers only go to 20%.