Whole House Fan Mounting Location Ceiling Quiet Design Yes Number of Speeds 2 Nameplate Voltage 120V AC Speed Controllable No Blade Diameter 18 in Drive Type Direct Drive Maximum Airflow 4 195 cfm Maximum Noise Level 1.7 sones Wattage 415 W Coverage Area 2 098 sq ft Rough Opening Type Square For High-Static Pressure Applications Yes High-Efficiency Motor Yes Number of Blades 3 Blade Material Steel Housing Material Steel Grille Material Aluminum Standards UL Listed