Description (Portable Mini 26dB Quiet) 300ml Portable Mini Humidifier can bring anywhere. Basically SILENT when it is running,less than 26dB (quieter tha library). Perfect for bedroom,plant and cup holder in car because they are always so dry.(Powered By USB) It is powered by USB, and the USB Power Supply compatible with any device USB port such as plug it into computer/car via USB.(Compact But Mighty)The tank holds a good amount of water for a night lasts 12-20 hours without refill . Shuts off automatically if out of water.(Two Mist Modes)The mist is super fine and can be adjusted in 2 different modeContinuous intermittentdisperses mist really well .No pools on the ground or condensed water anywhere.(Its A Life Saving Product)Doctor would recommended you to use a humidifier if you having nosebleeds and trouble breathing...Humidifier make surroundings humidified so that your life quality will be improved. Such as it can relieve your dry nose,dry cough,make you breath better,sleeping better and wake up refreshed.