Angle Flange Adapter For Nominal Duct Diameter 20 in Inlet Diameter 20 in Material Stainless Steel Product Type Angle Flange Adapter Material Thickness 20 ga Overall Length 5 in Maximum Pressure Rating 42 in wc Weight 19.15 lb For Duct Height 20 in Flange Inner Diameter 20 1/8 in For Duct Width 20 in Flange Outer Diameter 23 1/8 in Maximum Airflow 15 270 cfm Inside Diameter 20 in Number of Holes on Flange 12 Overall Width 23 1/8 in Bolt Circle Diameter 21 3/4 in