8 india Norm Opn Rnd Stel Zone Cntrl Dampr For Nominal Duct Diameter 8 in Damper Application Motorized Number of Panels Not Applicable Overall Height 4 5/8 in Overall Length 4 7/8 in Rough Opening Shape Round For Duct Shape Round Overall Width 8 in Frame Material Thickness Not Applicable Blade Material Galvanized Steel Maximum Air Pressure Not Applicable Overall Diameter 8 in Rough Opening Length 8 in Rough Opening Width 8 in Damper Type Dynamic