Standard Fan Assembled Assembled Blade Diameter 20 in Blade Material Steel Drive Type Direct Drive Duct Diameter Not Applicable Exhaust Airflow @ 0.000 in SP 3 440 cfm Frame Finish Powder Coated Frame Material Steel Guard Finish Powder Coated Guard Material Chrome Plated Wire Guard Type Intake Housing Material Steel Housing Finish Powder Coated Includes Steel Welded Box Guard Blade Maximum Noise Level 30 sones