Whole House Fan, Mounting Location Window, Quiet Design No, Number of Speeds 3, Nameplate Voltage 120V AC, Speed Controllable Yes, Blade Diameter 20 in, Drive Type Direct Drive, Maximum Airflow 3,560 cfm, Maximum Noise Level 4.6 sones, Wattage 170 W, Coverage Area 1,000 sq ft, Rough Opening Type Square, For High-Static Pressure Applications No, High-Efficiency Motor No, Number of Blades 3, Blade Material Steel, Housing Material Plastic, Grille Material Steel