Vent Hood For Nominal Duct Diameter 4 in Gas Appliance Category Category I For Duct Height 7 1/2 in For Duct Width 7 1/2 in Inlet Diameter 4 in Material Aluminum Overall Length 11 in Product Type Vent Hood Inside Diameter 4 in Material Thickness 20 ga Weight 7 lb Maximum Pressure Rating Not Applicable Maximum Temperature Rating 575 Degrees F Seal Material Not Applicable Standards Not Applicable Finish Flat Color Silver Overall Height 7 3/8 in Shape Rectangular Round