Mr. Kobayashi used this battery and ranked 5th in the Japanese 2012 F3C Championships.
Specs:
Capacity: 5800mAh
Voltage: 6S1P / 6 Cell / 22.2V
Weight: 763g+/-10g (including wire, and plug )
Discharge: 25C Constant / 50C Burst
Size: (L)155mm x (W)42mm x (H)50mm
Balance Plug: JST-XH
Suited to the following models:
550 size, 700 size, 800 size helicopter