WhisperValue® DC™ with multi-speed allows you to select the proper CFM settings to satisfy ASHRAE 62.2 code compliance for continuous ventilation requirements. As the lowest profile ENERGY STAR® rated ventilation fan available it is ideal for all types of residential and multi-family construction. Features our revolutionary ECM motor with SmartFlow™ technology to remove unhealthy air from any space. Pick-A-Flow™ speed selector switch enables you to customize airflow settings at your choice of 80 or 100 cfm.