This is a simple holder for a temperature and humidity sensor. This is very helpflull to monitor the temperature inside your enclosure while printing. You can get a sensor for as cheap as 1$ on Aliexpress. After printig I used double sided tape to stick to the ceilling. Info: the black "cable"in the picture behind the sensor is just the filament.

Aliexpress: https://www.aliexpress.com/item/32966936898.html?spm=a2g0o.productlist.0.0.32e518day6oUbt&algo_pvid=544ddee7-5df8-41b4-b0e6-a0cd6d5db25b&algo_expid=544ddee7-5df8-41b4-b0e6-a0cd6d5db25b-0&btsid=845c507f-95da-48ff-a935-96d239770c9f&ws_ab_test=searchweb0_0,searchweb201602_7,searchweb201603_53

Banggood: https://www.banggood.com/Mini-Digital-LCD-Temperature-Humidity-Meter-Thermometer-Hygrometer-Round-p-1164418.html?rmmds=search&ID=229&cur_warehouse=CN

Most expensive - Amazon.com: https://www.amazon.com/JEDEW-Hygrometer-Thermometer-Humidifiers-Dehumidifiers/dp/B07GR65CNT/ref=sr_1_13?keywords=thermometer+digital+LCD+hydro&qid=1575910965&sr=8-13