Hmm that's odd as I have the same ones though I haven't cracked mine open

http://hobbyking.com/hobbyking/store...dProduct=10277


Spec.
Minimum Capacity: 5200mAh
Configuration: 2S1P / 7.4v / 2Cell
Constant Discharge: 30C
Peak Discharge (10sec): 40C
Pack Weight: 333g
Pack Size: 139 x 46 x 26mm
Charge Plug: JST-XH
Discharge plug: 5.5mm Bullet-connector