The Sunbeam Cool Mist Humidifier brings comfort and relief to your dry home-environment. Water is passed through a filter to ensure clean, fresh mist is dispersed into the air. The Filter Check Dial lets you know when it is time to replace the filter. The removable tank makes it a breeze to clean and refill. At the turn of a knob, you can control the rate of humidity dispersed into the air for maximum personal comfort.