Humidifier Replacement Filter: Compatible with for Levoit ultrasonic humidifiers in LV600S / LV600HH / OasisMist600S / Superior 6000S / Classic160 / Dual 200S / Dual 150 / Classic 300 / Classic 300S / OasisMist450S model series. Please confirm your humidifier model before purchase Filtration Function: This humidifier replacement filter for levoit is designed to capture and filter fine impurities and particles, reducing water hardness and preventing white powder from entering the indoor air and being deposited wherever it is seen. Ensure the humidifier has higher humidification efficiency for healthier use Value Package: Each pack contains 20 x Humidifier Replacement Filters for Levoit. We recommend that you change the filters every 15-30 days for optimal humidifier performance (depending on water hardness). Also clean the humidifier at least once a week to ensure smooth operation Please note:the physical slightly color difference or difference, does not affect the use, please do not mind, thank you! Colour:Photo Color Material:Filter cotton Package Contents: 20 x Humidifier Replacement Filters Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.