"This Ventamatic Gable-Mount Power Attic Ventilator helps keep your home cooler while reducing energy costs. U.S.A. Amps 2.1, Needs to be Hardwired Yes, Fan Diameter in. 14, Depth in. 8, Volts 120, Speeds qty. 1, Dimensions L x W x H in. 15 x 8 x 15, Dimensions L x H in. 15 x 15, Air Delivery CFM 1,650. Reduces heat buildup in attic Prevents weather-induced home deterioration Equalizes temps inside and outside attic Galvanized steel construction For 2500 square foot attic Installs easily behind static gable louvers or CX2121 no holes in roof necessary Requires 600 square inches of free air exhaust vent area"