limited charge voltage : 4.40V rated capacity : 3900mAh/14.9Wh typical capacity : 4000mAh/15.3Wh normal voltage : 3.82V Li-ion battery do not allow the battery to damp or into the water. do not put the battery at full power after long-term preservation. donot imposed by external forces or fall from a height of the battery. do not put the battery heating or in fire, otherwise there is a risk of explosion. do not use bad charger, avoid charging dissatisfaction or damage the battery. do not key, coins, necklaces and other metal products, contact the battery, to prevent the occurrence of short circuit. IF satisfied with the product, kindly leave us a 5 star thank you for shopping!!!