Homedics UHE-WM65 Warm and Cool Mist Ultrasonic Humidifier Easy to remove and fill 1.7 gallon dual tank capacity Runs up to 72 hours per filling with auto shut-off protection when tanks are empty Ultrasonic technology for whisper quiet, visible, micro-fine mist with warm or cool options and built-in night light Clean Mist anti-microbial technology helps prevent the growth of molds and mildews on the surface of the tank Demineralization cartridge included