Beach RC says.... 

The ProTek R/C 4S 120C Graphene + HV 6500mAh LiPo Battery is a great battery option for anyone looking for a high capacity, high output 4S battery. Weighing 547 grams, the 4S HV is lighter than a standard 4S pack, with much higher capacity. This provides more runtime, and a dramatic increase in voltage and punch over the course of a run. 

When compared to standard LiPo and LiHV, Silicon Graphene cells deliver improved efficiency, lower operating temperatures, lower internal resistance, better run time, increased cycle life and increased voltage - but Graphene + 120C LiPo batteries take that a step further with more power and lower internal resistance when compared to the previous ProTek LiHV Graphene packs!

Lab testing has shown that ProTek R/C Silicon Graphene packs have double the cycle life when charged at 1C rates, and can be charged at higher amp rates, with less risk of damage to the pack. More importantly, the discharge curve is flatter, meaning the cells maintain higher voltage throughout the discharge cycle with no significant drop off. Additionally, when compared to conventional LiPo batteries Silicon Graphene batteries are lighter, providing a higher capacity per gram ratio. With 7.6V nominal voltage, 120C discharge ratings, incredibly high charge rates and ten different models to choose from, ProTek R/C 120C Graphene + packs are perfect for racers and bashers that demand the absolute best.

• Replacement XH4S balance adapter also available separately