This package includes 10 humidifier replacement filters designed for Levoit humidifiers. These filters work with ultrasonic Levoit humidifiers in the LV600S, Dual 200S, Dual 150, Classic 300S, and LV450S (Oasis Mist) model series. They function by capturing and filtering fine impurities and particles to ensure higher humidification efficiency and healthier use of the humidifier. It is recommended to replace the humidifier filter approximately every month, depending on the hardness of your water. Levoit humidifiers help maintain a healthy air humidity level in your home and improve your breathing comfort. Each filter weighs 0.0881849048 pounds.