This humidity sensing fan detects rapid increases in moisture levels at the ceiling level and triggers the fan to turn on and off. The sensing fan can assist in preventing the cosmetic and structural problems associated with excess moisture. The auto shut-off time is adjustable from 5 to 60 minutes. Hanger bars allow this fan to be easily installed. UL listed when connected to a GFCI protected branch circuit. This design connects with 6" ducting. White finish. Motor loudness rated at 0.9 sones. Air movement rated at 110 CFM.