Galvanized Housing Resists Humid Conditions and Changing Attic Temperatures, Unlike Plain Steel Housing Used in Many Vents. Housing has Ceiling Thickness Indicator Markings and Built-In Mounting Tabs for Quick Installation. Attractive Molded Grille with Spring Clips for Smooth Fit Against Ceiling. Dishwasher Safe Grille for Easy Homeowner Cleaning. Easy Remove and Install Motor Assembly with Keyhole Mounting Bracket. Permanently Lubricated Motor with Plug for Quick Activations. Built-In Junction Box for easy wiring. Molded Fan Blade - Precision Balanced for Quiet Operation. Molded Duct Adaptor with Built-In Damper. 1,100w Fan Forced Heating Element.