Duct Collar w/Damper For Nominal Duct Diameter 8 in Material Steel Overall Length 5 in Material Thickness 26 ga Weight 1.68 lb Maximum Pressure Rating 3 in wc For Duct Height 6 in Shape Round End Type Crimped For Duct Width 8 in Gas Appliance Category Not Applicable Inlet Diameter 8 in Damper Type Low Leakage Inside Diameter 8 in Flange Outside Diameter 1 in Outside Diameter 8 in Flange Inside Diameter 8 in Color Silver Outlet Diameter 8 in Overall Height 6 in