This battery backup will keep your smartphone charged up when needed. With a 4,000 mAh Grade A Li-Ion battery and a 5V/1A output this charger will fully charge an iPhone about 1.5 times giving you an additional 12 hours of talk time. It also includes an LED light and battery test button, making sure you know how much battery life you have left. Includes a USB to Micro USB connecting cable which can recharge the battery backup or be used to charge up devices with a Micro USB input like Android Smartphones