6 In.dia GSteel Manual Control Dampr Damper Application Control For Nominal Duct Diameter 6 in Frame Material Steel Number of Panels 1 Maximum Air Velocity 3000 fpm Overall Height Not Applicable Rough Opening Diameter 6 in Rough Opening Shape Round Fits Fan Diameter Not Applicable For Duct Shape Round Overall Width Not Applicable Frame Material Thickness 20 ga Overall Length 14 in Connection Type Not Applicable Frame Depth 8 1/4 in Rough Opening Length Not Applicable