Non-Duct Kits Help To Recirculate Air In Situations Where A Hood Must Be Installed As Ductless. Change Filters Regularly To Keep The Kitchen Fresher. (Ul)(Li)For Use With Wcn1 Series Chimney Range Hoods(/Li)(Li)Kit Includes 8″ Round Metal Flex Duct, Diverter And Filters(/Li)(Li)Uses Non-Duct Replacement Filters S99010512 (Pack Of 2)(/Li)(/Ul)