Portable Handheld Fan DOIOWN USB Mini Table Desk Personal Fan with 4000mAh Rechargeable Power Bank For Travel Outdoor Pool Car Desk (4000mAh portable charger&black) Special Portable Design --- DOIOWN Portable Handheld Fan made of high quality ABS material. Its compact, cute, lightweight and foldable. Perfect for using in hot weather, travel or any outdoor events. NOTE: Some of our customers reflected the battery and fan don't fit very well. Please note there is a cover at the end of battery. Only you take it away to install the fan then they will fit properly. Efficient & Functional -- Powerful three mode allow you choose different speed of wind. Back hook design apply to the umbrella while walking; The metal clip specific design for the pram and camping use. How to install -- 1.Press the button at both side of power bank to take the cover off.2.Hold the button again to intall the fan to the power bank.3.Press the button on power bank to turn on the power then press the button on the fan to turn on. 3.Press the button for 4 times to turn down the fan. Rechargeable Battery & Excellent Battery life --- DOIOWN mini fan comes with a 4000mah portable charger you can charge it by USB charger, computer. You could have the power bank full charge only 4.5H and it could work 5-20H. Shop With Confidence -- We offer an 18-Month Warranty. If you have any questions, please feel free to contact us, our customer service will be more than happy to assit you.