Schoolsupply Mini Bottle Cap Design USB Ultrasonic Humidifier Air Diffuser for for Office Travel Home Room Bedroom Desk Car Vehicle Through diffusing water mist, it can increase air moisture and removes the dust in the air molecules. Mister cool off by using cold water. This environmentally-friendly humidifier helps reuse bottles & has a low power output of 2 watts. Whisper-quiet ultrasonic operation with LED light, constantly working for 6 hour with bottle full filled by water Convenient to use anytime, anywhere, this personal-use humidifier is small enough to fit into a purse, laptop bag, or suitcase etc. Included with the humidifier are 2 filters (one installed) & a USB cable. To assemble, insert the filter into the underside of the humidifier, then plug the humidifier into the USB cable & the USB cable into a USB port.