Exhaust Fan, Assembled Assembled, Blade Diameter 20 in, Blade Material Aluminum, Drive Type Direct Drive, Duct Diameter 20 1/2 in, Exhaust Airflow @ 0.000 in SP 3,456 cfm, Frame Finish Galvanized, Frame Material Steel, Guard Finish Zinc Plated, Guard Material Steel, Guard Type Intake, Includes Dehumidistat No, Maximum Noise Level 17.4 sones