This is the 5000mAh 4S Battery and EZ-Peak Live 12-amp NiMH/Lipo Fast Charger with iD from Traxxas.The #2996X 4S Completer Pack delivers ultimate power to your Maxx® for the speed and acceleration you crave. Punch the throttle and the 4-cell 5000mAh iD LiPo battery lights up the tires for blistering 60 mph speeds and long run times. Traxxas iD batteries are the easiest and safest Lipo charging solution when used with our exclusive iD chargers. You just plug in your iD battery and press start. The iD charger handles all the settings and quickly gives you an optimized charge every time. The new 4s capable EZ-Peak Live multi chemistry charger comes equipped with built-in Bluetooth to work with the new EZ-Peak Live™ app for iOS and Android. The app gives you detailed information and advanced operation through a high-definition color interface. It’s our finest charger in the popular EZ-Peak iD lineup.