Whole House Fan, Mounting Location Ceiling, Quiet Design Yes, Number of Speeds 2, Nameplate Voltage 120V AC, Speed Controllable Yes, Blade Diameter 30 in, Drive Type Direct Drive, Maximum Airflow 4,425 cfm, Maximum Noise Level Not Applicable, Wattage 150 W, Coverage Area 3,000 sq ft, Rough Opening Type Square, For High-Static Pressure Applications No, High-Efficiency Motor No, Number of Blades 4, Blade Material Aluminum, Housing Material Steel, Grille Material Aluminum, Standards C-UL