Power Supply: USB Voltage: DC 5V Power: 2W Water Capacity: Approx. 180ml Spray Quality: 30ml/h Size(Dia x H): Approx. 80 x 120mm / 3.15 x 4.7inch Our ultrasonic humidifier is used for increasing air moisture for good breathing and air-fresh. It also can help you to prevent dry skin, eyes and nasal passages. When you want to use it, connecting the USB cable to a computer or a mobile power product, then it will provide a consistent stream of water vapor. It has small body, so it is very convenient to move and it takes very little space. So such a practical air humidifier, worth buying!