3-5 In.dia SS Barometric Draft Control Damper Application Barometric Draft Control For Nominal Duct Diameter 3 in 4 in 5 in Frame Material Steel Number of Panels Not Applicable Maximum Air Velocity Not Applicable Overall Height 4 5/8 in Rough Opening Diameter 4 in Rough Opening Shape Round Fits Fan Diameter Not Applicable For Duct Shape Round Free Area Not Applicable Overall Width 4 5/8 in Frame Material Thickness 22 ga Overall Length 7 in Connection Type Press Fit