depends on where you buy,the white one is 10,400mAh and can barely fully charge my 3,000mAh lumia battery,bought it at ebrahims electronics for 1,700/
notice the box says 2,900,that guy said f**k the mhindi i didnt even get a receipt,now i know why the black one is more than a year old at 8,400mAh and charges at least 2.5 times which is accurate enough cost me 2,200/ lakini wife ali hijack thus i bought the white one like 2 months ago,
