This is the Traxxas 6400mAh 11.1V 3C 25C LiPo with Auto Battery iD TRA2857X.

Features:
iD Technology
Semi rigid construction does not require a hard case and eliminates wire harness connectors that can loosen and fail
Engineered specifically to fit Traxxas models
12AWG multi strand wire is soldered directly to the LiPo cells eliminating increased resistance from bullet connectors and accidental reversed polarity connections
Requires:
EZ-Peak Plus 4-amp NiMH/LiPo Fast Charger with iD™ Auto Battery Identification
LiPo charging bag
Specs:
Configuration: 3S2P
Continuous Discharge: 25C (160A)
Max Burst Rate: 50C (320A)
Watt Hours: 71.04
Charge Rate: 1C (6.4A)
Max Charge Rate: 2C (12.8A)
Dimensions: 5.3 x 1.6 x 1.8" (135 x 42 x 45mm)
Weight: 17.1oz (485g)