EVDH 30 to 130 CFM Variable Speed ECO Humidity Sensing Exhaust FanAir Kings ENERGY STAR certified variable speed ECO humidity sensing exhaust fans provide barely audible sound levels, effective and efficient automated ventilation. The integrated humidistat senses the humidity level of the room and turns the fan on until the humidity level is below the preset percentage. Humidity level can be set up to 80% relative humidity. Plus, the 8 capacity settings on low speed allow the fan to be set to the required exhaust