DAYTON 484X44 ShtterMnt ExhFn,20In Bld Dia,Alum,115 V 484X44 Shutter Mount Exhaust Fan, Assembled Assembled, Blade Diameter 20 in, Blade Material Aluminum, Drive Type Direct Drive, Duct Diameter Not Applicable, Exhaust Airflow @ 0.000 in SP 4,034 cfm, For Cut-Out Height 21 in, For Cut-Out Width 21 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 20% RESTOCKING FEES AND SHIPPING WILL BE CHARGED. IF ITEM IS FUNTIONAL OR INCOMPLETE. Your feedback is extremely important to us! If you are satisfied with our service please take the time to give us positive feedback. We tremendously appreciate it! We strive for your complete satisfaction. Likewise, if you have any issues, please contact us first, and we promise we will do our best to satisfy your needs and solve the problem. If we resolve your problem, we kindly ask you to still leave us positive feedback. Your kindness will be extremely appreciated!