18650 battery is a Li-ion rechargeable battery with 2000 mAh Battery Capacity. This is not a standard AA or AAA battery but is very useful for applications which require continuous high current or high current in short bursts like in cameras, DVD players, iPod, etc. A 18650 cell can be charged and discharged up to 1000 cycles without much loss in battery capacity. They are safe to use, environment friendly and has a long battery life. It comes with high energy density and provides excellent continuous power sources to your device. It should be used with a protection circuit board which guards the battery against over-charge, over-discharge of the pack, and avoid over-current drawn. Important: Please note that, this cell is a copy version and is not original, hence the capacity and performance of the cell might vary based on charging and discharging parameters in your application. We do not recommend this for power critical applications. You can check out Original Hongli 18650 cells for demanding applications Specifications Voltage: 3.7 Voltas Capacity: 2000 mAh Rechargeable: Yes Battery Size: Diameter- 18mm x Length- 67mmn Charging Method CC-CV