Specification: item/Spe: NP-IP4A Normal capacity: 1600MAH Real capacity: 1600MAH Output voltage: 5V Output current: 500MA Input voltage: 5V Input current: 500MA Charging time: 3 ~ 4 hours Colour:black and blue Accessories: USB line, Iphone 4G protective coverings Description: 1. Battery + protection cover , solving the signal problem perfectly 2. Whith data transfer function , connected with PC and iTuners synchronous. 3. Equipped with intelligent switch ,extended the built-in battery service life, thereby guarantee the security 4. Accurately display electronic capacity , the LED light will be flicker when low capacity. 5. Full covered packing design, perfect fit for iPhone4. 6.Standby time:≥400 hours 7. Holding time: over 7 hours by 3G net / over 13.5 hours by 2G net 8. Online time: over 7 hours by 3G net / over 8 hours of Wi-Fi using. 9. Music play: over 30 hours 10. Video play: over 8 hours