3.7Volt 2000mAh Rechargable Battery. This Standard 18650 2000mAh 3.7v Rechargeable Li-Ion Battery is a single cell compact and powerful battery cell with 2000 mAh capacity. This Li-ion battery is very convenient to install in your project where 3.7 Volt with high capacity is needed. The Standard 18650 2000mAh 3.7v Rechargeable Li-Ion Battery is a source of power for various portable devices including flashlights, hobby transmitters, and receivers etc. This Battery can be a best Replacement to the normal Non-Rechargeable AA Battery used in many application such as in RC Transmitter/Reciever Remote, which can make your flight driving experience very cost effective and Efficient in terms of power Output than that of conventional AA batteries.