Samsung EB-F1A2GBU Battery for Samsung i9100 Galaxy S2, Galaxy S2 I9100 (1650 mAh / 3.7V) - original packaging (Electronics)
I highly doubt this evening an official seen as packaging and 2 times larger than the thing battery that will not let go Samsung but for now it does what he is asked to say c to turn the phone for 1 day but not more ..