The 5,000 mAh keychain-sized USB Backup Battery provides maximum portability without sacrificing functionality and features. This 1-amp 500-milliamp charger provides power to your mobile device via dual USB ports with auto shutoff, preventing overcharge. The battery-level indicator make this Backup Battery a must-have.BDSIGPH50W. IGPH50W. Gonplug GONPLUG GP-H50W 5,000 mAh Dual-USB Backup Battery (White).