Battery Power USB Portable Emergency Charger for Iphone Ipod Android HTC Samsung Blackberry Sony-ericsson 1.High quality external emergency charger. 2.Easy to use, just plug and charge. 3.The charger itself doesn't need to be charged, it is powered by two AA batteries. (Batteries are not included in the package). 4.Input voltage: 2.0-4.2V 5.Power supply: 2 * AA batteries (Batteries are not included)