Traxxas 3037 NiMH 5-Cell 6V 1200mAh Receiver Battery (hump pack) Replaces stock AA battery packs in Traxxas nitro vehicles More power and longer run times than stock AA battery packs Rechargeable receiver packs save money in the long run Helps reduce glitches caused by weak AA batteries J Style Connector 1100 mAh battery Hump configuration