ANLENG 4-inch Mini Rechargeable Portable Fan (Black) Mini 4 inch design, so portable, just put into your bag, and use it anywhere. Battery type: Li-ion 18650, high efficient, 2-8 working time (depend on speed). Dual power source, plug in with the USB adapter or use with the battery. 3 speed settings. LED light on side for emergency illumination. Ideal for indoor and outdoor using.