2pcs Acatim 14500 750mah 3.7V Rechargeable Li-Ion Battery (Pair) + Charger Combo For Ultrafire Q5 LED Flashlight Genuine 750mAh 14500 Li-ion Rechargeable Battery , not fake Capacity Holds 85% of it's charge over 12month period Can be charged over 500 times Can be used on Ultrafire Q5 flashlight Lighter than standard alkaline battery