Broan® AE50110DCSL Flex DC™ Series 80 CFM Humidity Sensing Exhaust Bath Fan, ENERGY STAR® offers easy, room side installation, with “No Attic Access Required”. Ceiling mounted ventilation fan features foldable mounting ears and EZ Duct connector for easy installation. New duct damper technology provides a tighter seal, resulting in reduced warm and cold air backdrafts. The humidity sensing feature will automatically turn the fan on when a preset level has been reached, thus allowing for proper ventilation throughout the room. This energy efficient fan operates at a selectable CFM range of 50-80-110 at a quiet operation of <0.3-0.4-0.9 sones.