Use Ni-MH compatible charger
Get long life and plenty of power with the HPI GT 7.2v 3300mAh nickel-metal hydride rechargeable battery pack. With its massive capacity you’ll be running far longer than before, enjoying its fully 7.2v power!
Perfect for the E-Firestorm off-road truck, the E10 drift and touring cars, the E-Savage electric monster truck and the complete range of HPI Roto Start 2 or original Roto Start engine starting systems!
Supplied with standard RC battery connector. Charge only with a Ni-MH compatible charger.
Source : HPI