Miele DuoFlex HX-FDF 20 FIlterProduct Information Fine dust filter filters even the smallest dust particles from the air Pleated material catches ultrafine dust particles Filter pre cleaning using the ComfortClean feature To maintain appliance performance, change filter every 3 years Supplied without lid use the lid from the filter you are replacing Compatible with Duoflex cordless stick vacuum cleaners Active AirClean filter. Active AirClean filters for excellent air quality.