APGH Gable Mount Power Attic Ventilator, 1620 CFM, Ventilates Up To 2300 SQFT, With Adjustable Thermostat From 60 To 120 Degrees & Adjustable Humidistat From 20% To 90%, Thermostat Runs Fan In Summer, Humidistat Runs Fan In Winter, 15" Diameter Housing, 14" Diameter Fan Blade, 3.7 Amp Motor, 4 Bladed Fan Blade, Needs 778 SQIN Of Net Free Intake Air, For Fan Shutter Use True Value #102319, 10 Year Manufacturer Limited Parts Warranty, 5 Year Manufacturer Limited Labor Warranty.