2S4000DX8PCM: 7.4v 4000mAh Li-PO battery for SPEkTRUM transmitters, SPMB4000LPTX BP-7 insert 1650mAh Ni-MH

1650mAh Ni-MH

Panasonic Lumix DMC-FZ50K

Empire: CPH-518D

It has a coaxial plug -  Center Polarity NEG(-) - which plugs into the DC jack on the battery pack

2S4000DX8PCM: 7.4v 4000mAh Li-PO battery for SPEkTRUM transmitters, SPMB4000LPTX BP-7 insert 1650mAh Ni-MH2S4000DX8PCM : 7. 4volt 4000mAh rechargeable Li PO battery pack for SPEkTRUM RC transmitters such as DX7s, DX8, DX9, and also the newer DX6 & DX7 transmitters that can accommodate the SPMB4000LPTX square LiPO battery. Includes built in PCM, for smart balance re charging while installed in the transmitter. Also has built in safety current circuitry, to prevent overcharging. Replaces original SPEkTRUM battery SPMB4000LPTX. Dimensions: Length: 2.