Shutter Mount Exhaust Fan Assembled Assembled Blade Diameter 30 in Blade Material Steel Drive Type Direct Drive Duct Diameter Not Applicable Exhaust Airflow @ 0.000 in SP 5 090 cfm For Cut-Out Height 31 in For Cut-Out Width 31 in For Maximum Wall Thickness 6 in For Minimum Wall Thickness 3 in Frame Material Aluminum Guard Finish Powder Coated Guard Material Steel Guard Type Intake Housing Material Aluminum Steel Housing Finish Powder-Coated Includes Intake Guard