The Faithfull Replacement Battery For FPPSLLED30TB, used to provide extended run time, using an additional battery allows the battery packs to be cycled as they become exhausted and is particularly useful when no other power supply is available. The battery can be independently charged using either the mains or car charger that is supplied with the lamp (FPPSLED30TB) and can also be recharged in the lamp when it is in use with an external power source.