Pro Breeze Ultrasonic Cool Mist Humidifier, 1 Gallon (3.8L) - Works for up to 40 Hours, Whisper-Quiet, Automatic Shut-Off, and Night Light Function ULTRASONIC COOL MIST – The humidifier safely releases moisture into the air for up to 40 hours, helping you to breathe easier and enjoy a better night’s sleep – The fully adjustable dial lets you choose the perfect speed for cool soothing mist to be released into your room. INTEGRATED CERAMIC FILTER – A ceramic ball filtration system removes impurities from the water before it is vaporized, providing you with clean hydrating mist. LED NIGHT LIGHT – At the click of button your humidifier can turn into a relaxing night light perfect for children and babies bedrooms. A removable essential oils tray can be used to add a subtle scented mist throughout your room. 360° NOZZLE ROTATION – The fully 360° rotating nozzle allows you to direct cool mist into any direction you desire, making it perfect for bedrooms, bathrooms, offices and other medium sized rooms. UP TO 40 HOURS CONTINUOUS OPERATION – The large 1-gallon water tank allows the humidifier to run continuously for 40 hours. The whisper quiet operation allows it to be on all night without causing a disturbance, helping you have a great night’s sleep.