7 In.dia SS Barometric Draft Control, Damper Application Barometric Draft Control, For Nominal Duct Diameter 6 in; 7 in, Frame Material Steel, Number of Panels Not Applicable, Maximum Air Velocity Not Applicable, Overall Height 7 5/8 in, Rough Opening Diameter 7 in, Rough Opening Shape Round, Fits Fan Diameter Not Applicable, For Duct Shape Round, Free Area Not Applicable, Overall Width 7 5/8 in, Frame Material Thickness 22 ga, Overall Length 9 5/8 in, Connection Type Press Fit