The Frigidaire Undercabinet 36" Ventilation Hood Features A Filter Indicator Light That Reminds You When It'S Time To Replace Your Carbon Charcoal Filter To Continue Capturing Odors And Circulating Fresher Air. Also Offers Led Lighting That Illuminates The Cooktop, Soft Touch Controls That Make Selecting Fan And Lighting Options Easier, And The Dual Speed Fan That Recirculates Air At 220 Cfm.