Angle Flange Adapter For Nominal Duct Diameter 17 in Inlet Diameter 17 in Material Steel Product Type Angle Flange Adapter Material Thickness 20 ga Overall Length 5 in Maximum Pressure Rating 42 in wc Weight 12.9 lb For Duct Height 17 in Flange Inner Diameter 17 1/8 in For Duct Width 17 in Flange Outer Diameter 20 1/8 in Maximum Airflow 11 030 cfm Inside Diameter 17 in Number of Holes on Flange 8 Overall Width 20 1/8 in Bolt Circle Diameter 19 in Minimum Pressure Rating 2 in wc