Broan 639 3-1/4" x 10" Duct Black Wall Cap with Damper
Wall Cap - Model 639 For 3 1/4" X 10" Duct Spring-Loaded Backdraft Damper Built-In Bird Screen Steel Baked Black Enamel Finish 24 Ga Crcq Steel, Black Electrically-Bonded Epoxy Finish