Happy-top 360 Degree Adjustable Wireless USB or 18650 Battery Powered Portable Desk Fan Mini Portable Fan Electric Personal Table Fans Stepless Wind Speed Adjustment (Blue) You can be free to turn down or turn up air volume with the stepless speed technology. Powered supply can be USB or international standard 18650 battery;more convenient. Using the brushless motor and improved PVB,ensured the super wind and life. Intelligent control system,reliable performance multifunctional,easy for operation. Rechargeable batteries make the Clip fan suitable for anywhere indoors and outdoors in summer.