With the Philips Air Performer 4-in-1 9000 series Humidification Filter, you can keep the air in your home pleasantly humid. This replacement filter is for the Philips Air Performer AMF971/00. The filter absorbs water and spreads it through the room as a fine mist. This helps prevent dry air around your nose, skin, and eyes. Replace the humidification filter once a year so it keeps working properly. Always check the model number of your device before you buy to make sure you get the right filter.