3S LED Color Mini USB Air Mist Humidifier for Bedrooms, Living Rooms,Car,Home and Office This mini USB diffuser is designed for small area such as the office desks. It's powered by a USB interface which could be the computer or a power bank. USB-Powered, it's easy to use and simple design,can increase air humidity,clean air, smoke and dust 120ml water tank, 3 blue LEDs and a adjustable knob for mist. Low power consumption and power-off protection when the water runs out. This personal humidifier offers portability that is suitable for travel use. Perfect for use at bedrooms, living rooms, children' room, car, home and office.