LiFePO4 6.6V 2080mAh TRANSMITTER PACK, for Futaba 4PK and similar tranmsmiters using 5-cell (6.0V) NiMh flat packs. Includes Safety PCM circuits to allow charging inside Transmitter, using standard wall NiMH charger.
These are LiFePO4 Transmitter Power Packs, with high-rate 3.5mm gold charge/discharge plugs, and Hyperion-style Balance Tap.
See DATASHEET for full specifications and usage guidelines.
CLICK HERE to see datasheet
" I recomend you use your Lipo charger set on the LiFe setting to charge these"
These will work in the Graupner Mx-20. However they do get a bit higher voltage than Graupners recomdation.
You need the adapter Cable listed under related products to plug and play with your radio.
These work much better than the NiMH battery that comes with the radio. Longer life and shorter charge.
I hate NiMH bateries..:)