Complete your duct fan install with these Adjustable Metal Exhaust Grilles by Fan Tech. The grilles come with a metal mounting collar and have a White powder coat finish. Included with the grille is a matching diameter galvanized mounting collar with nailing strip. The grills are available in sizes to fit 4" to 8" duct. The MGDE models include integrated backdraft damper. Ships via UPS/FedEx Ground.