This is the Thunder Power Pro Power "G4" 45C, 3S, 11.1V, 2250mAh Li-Polymer Battery. The 3S 11.1V 2250mAh battery is the most powerful battery ever made available for powering 400/450 class helicopters and park flyer EDF models, offering up to 40% more power and up to 6-times more cycle life than the previous generation 3S 11.1V 2200mah eXtreme V2 battery.

Specifications:
Type: Lithium Polymer
Capacity: 2250mAh
Voltage: 11.1V nominal
Number of Cells: 3
Weight: 193 grams
Configuration: 3S
Dimensions (LxWxH): 102x35.0x26.0mm
Maximum Continuous Discharge: 45C (101A)
Maximum Burst Discharge: 90C (202A)