This is the Dynamite 7.4V, 2S, 2000mAh Li-Poly 30C Long Battery Pack, with an EC3 Connector.
Specifications: Type: LiPo
Capacity: 2000mAh
Voltage: 7.4V
Connector Type: EC3
Wire Gauge: 16AWG
Configuration: 2S1P
Length: 3.93 in (100mm)
Width: 1.20 in (30.5mm)
Height: 0.73 in (18.5mm)
Maximum Continuous Discharge: 30C
Maximum Burst Discharge: 60C