Intellect 2000mAh 8-Cell NiMH Transmitter Battery Pack with JST Connector (see details) - Block Configuration of 2x2 cells double long. Replaces wimpy 600mah transmitter batteries and provides more than 3 times the capacity. Made with the super-capacity IB 2000mAh cells, you can be assured of quality control and reliable operation from this professionally-assembled pack. Fits all Transmitters which use similar pre-made AA packs of same shape, such as Hitec, mostJR, Airtronics, and many Futabas. Pre-installed two-pin JST connector fits virtually any transmitter as it is. Just check the connector arrangement on your stock pack and be sure to connect the new pack with proper polarity. (note: photo shows Futaba-type connector, but this is changed to 2-pin JST for greater compatibility with all brands)