Long Working Hours---20000mAh large capacity battery. When fully charged, it can work for 200 hours in low-speed mode. You can monitor the remaining power according to the indicator light. Emergency Power---When you encounter a power outage or emergency, this personal fan can act as your mobile power supply. With a USB interface, you can charge the phone or use an emergency light source. Very suitable for outdoor camping. Shutdown Timer---When you need cool breeze to help you fall asleep. You can use the timer function of the desk fan. Set to turn off after 2 hours/4 hours. Avoid catching cold when you fall asleep. 3 Speeds---This desktop fan can be set to 3 wind speeds. Low wind speed can reach 2.4m/s, high wind speed can reach 4.5m/s strong wind. The fan can rotate vertically at 350 angles. Working time is 15-200 hours. Elaborate Design---It's not just a desktop fan. It also has the function of mobile power. It measures 9.4 x7.1x2.8 inches and weighs 1.56 pounds. Comes with a handle for outdoor use. Wonvin brand creations and products glow the essence of elegance and luxury.