Hazardous Location Exhaust Fan Assembled Assembled Blade Diameter 16 in Blade Material Aluminum Drive Type Direct Drive Exhaust Airflow @ 0.000 in SP 3 220 cfm For Cut-Out Height 20 1/2 in For Cut-Out Width 19 1/2 in For Maximum Wall Thickness 10 in For Minimum Wall Thickness 2 in Frame Finish Polished Frame Material Polyethylene Guard Finish Powder Coated Guard Material Steel Guard Type Exhaust Hazardous Location Class Class I Div 1 Group C and D Class II Div 1 Group F and G