USB Mini Fan,ChYu@ 4-inch 3 Speeds Portable Electric Desktop Fan Battery/USB Powered Laptop Fan with Battery and USB Charge Cable (Black) Portable mini fan powered by Built-in lithium battery; convenient to carry anywhere and anytime. RECHARGEABLE BATTERY: tired of constantly replacing fan batteries after little use.Our Fan is designed with an ultra high performance, 3.7v USB rechargeable Li battery offering up to 8 hours of uninterrupted cooling, for the longest lasting, high performance Mini Fan on the market! Charger cable length:27CM, about 10.63 inch.But you can use other micro USB cable to charger if you think the cable is short. Intelligent control, the function is perfect, the operation ifs simple,stable and reliable performance. Built-in high capacity lithium battery, charging circuit, low use cost. Note:Fan can't be worked without lithium battery in.