CAPACITY: 4000 mAh?? Li-Polymer Battery?? 5V Input/Output. 76 Hrs Audio?? 13 Hrs Video?? 11 Hrs Wi-Fi Browsing?? 11 Hrs LTE Browsing?? 23 Hrs Talk added w/ 365 Hrs standby. Apple Certified: Made for iPhone</br>PROTECTION: Durable?? changeable frames adding double external protection. Power Case protection against short circuit and over charge</br>CHARGE & SYNC: Charge your iPhone and Case at same time w/ out having to removing one from another. It will automatically charge your iPhone first until it is at 100% and then start the Battery Case</br>FEATURES: Changeable frames?? Power Buttons in back?? LED indicator?? Full Accessibility to buttons and camera?? Built in Li-Polymer Battery?? Lightning Connector?? Micro U