Spektrum Lipo Akku 4000mAh Lipo DX7s, DX8, DX9

4000mAh LiPo Transmitter Battery: DX7s, DX8, DX9
Key Features

* Built-in cell balancer
* Built-in safety current prevents over charging

Overview

The 4000 2S LiPo offers not only double the flight time as the stock
DX8 battery but also advanced safety and features. It also includes a
built in safety current that shuts the battery, to avoid overcharging and
damaging the battery and radio. Plus a built in balancing system to
make sure you get the longest life and power from your pack.