have always been Lipo 6750mAh 4S - 14.8V 55C constant 110C 5mm Bullets (Si-Graphene) Design for anyone 10 min long main. The hardcase battery weighs in at 534g. just about 2 light weigh LCG pack battery. Ideal for outside 1/8th scale Racing. Brand new bullets connector make wiring more pro. Design to undertake tall KV score motor.