The thermistor decreases the current resistance as it gets hotter. The printed circuit board sends a current to the thermistor and can tell whether less or more heat is needed by the relative resistance in the thermistor.
Comes with Screw
Technical specification
Product TypeClipTypeClipsToilet Cistern CapacityFTW--ERP RatingNot ApplicableSupplier Part Number87161483130Brand NameWorcester Bosch