The F40000 series provides installation flexibility with 4-way convertibility to fit virtually all applications. The hood is designed for under cabinet use and installs as 3-1/4 in. X 10 in. Ducted opening with vertical or horizontal ducting; or 7 in. Round vertical ducting or as non-ducted with air recirculation. The hood features a fan designed for years of trouble free service, an easy to clean grease filter, a protective lamp lens that distributes light evenly over the cook top and control switches for fan speed and light activation.