The official 7.4v lipo battery by Umarex/Elite Force. Designed to be able to fit into AEG M4 buffer tubes. This lipo has a 1500mah capacity and comes fitted with a tamiya connector out of the box for your gun and a balance plug to charge. This is a 15c output lipo to make sure it falls within warranty with most airsoft manufacturers & distributors.
Please be careful when using lithium polymer batteries such as this one. If you haven't used one before make sure to educate yourself on how to take care of your lipo battery. 11.1v batteries are designed for higher end setups and can put extra wear and tear on your gun. Some gun warranties are voided with the use of a lipo battery, check your owners manual. Do not use once the battery starts to run low. You will audibly and visually see your gun performing difference, when that occurs discontinue use and charge your battery.