4.8v 6v 9.6v AA 2500mAh Vapex Instant Receiver Transmitter Handset Battery Pack

4.8V 2500mAh AA - Flat. 4.8V 2500mAh AA - Square. 6V 2500mAh AA - Flat. 6V 2500mAh AA - Hump. 9.6V 2500mAh AA - Flat. always best to go a little lower than this - it will improve the life expectancy of the battery.

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