The QS3 Series offers unmatched style, quiet, and ease of use. This range hood model combines handy features such as three-speed soft touch electronic control plus boost speed, and a delay-off option. Ultra quiet performance of .4 sones at normal speed with an extra powerful 430 CFM boost capacity. The "Clean filter" reminder makes remembering to put professional style aluminum filters in the dishwasher simple, while dual halogen lighting improves cooktop visibility. The easy-to-clean DuPont Teflon® bottom pan and fully enclosed design makes it easy to keep your range hood looking like new. Ducted or non-ducted recirculation capability makes installation easy in most any applications. 3-1/4 in. x 10 in. adapter/damper and 7 in. round adapter included, optional 7 in. round damper (BP87) to prevent backdrafts sold seperately. For non-duct recirculation replaceable charcoal filters are available that simply clip on to the back of the grease filters, sold seperately.