This is the Traxxas SERIES 5 5000mAh 8.4V 7C Hump NiMH with iD Technology.

Features:
12AWG multi strand wire is soldered directly to the LiPo cells eliminating increased resistance from bullet connectors and accidental reversed polarity connections
Semi rigid construction does not require a hard case and eliminates wire harness connectors that can loosen and fail
iD Technology
Engineered specifically to fit Traxxas models
Requires:
EZ-Peak Plus 4-amp NiMH/LiPo Fast Charger with iD™ Auto Battery Identification
LiPo charging bag
Specs:
Type: Nickel Metal Hydride - NiMH
Capacity: 5000mAh minimum
Voltage: 8.4V
Connector Type: Traxxas High Current
Wire Gauge: 12
Number of Cells: 7
Configuration: Hump

Traxxas Bandit
Traxxas Drag Slash
Traxxas Hoss
Traxxas Rustler
Traxxas Rustler 4x4
Traxxas Stampede
Traxxas Stampede 4x4