I purchased this to replace the AA battery holder that comes installed in my Spektrum DX6E transmitter (SPMR6655) since I don't like to waste money purchasing AA batteries. I looked into rechargeable batteries before purchasing this, but I decided to purchase this Li-Ion battery since it provides a higher voltage to the transmitter. Some have claimed that installation in the DX6e was difficult, however I did not find that to be the case. Simply remove the foam surrounding the existing AA battery holder, unplug and remove it, then plug in the Li-Ion battery and slide it into place. This process required no tools and took less than five minutes. Once it was installed, I also removed the foam from that back of the battery hatch as I could not fasten it without doing so. The existing covered hole on the battery hatch lined up perfectly with the battery's charging terminal so that it can be charged without opening the battery hatch. The AC charger that is provided performs as it should, however I have three criticisms about it. First, the AC charger does not include a light to indicate when your battery is fully charged. To see that, you will need to turn your transmitter on, which can be annoying. Secondly, the connector that plugs into the battery is straight rather than the elbow type. I prefer elbow connectors since the point where the wire enters the connector is the weakest link and an elbow-type connector reduces stress at that junction. Lastly, the charger comes with four adapters to accommodate a variety of power receptacles. To me, this seems to be a waste, as in the US market, only one type of plug is needed. It seems that the type of receptacle plug could be offered as a choice to reduce the cost.