Charge your Micro-USB ready device on the go with the TYLT Zumo! Portable standalone 1500mAh battery pack. Provides up to 5 hours of additional talk time. Capable of providing you iPhone 4 with an additional 65% charge. Has everything you need built right onto the unit. Built-in Micro-USB arm allows you to charge your phone anytimne, anywhere. Easily recharge the Zumo by plugging in the on-board USB connector to any USB power source such as a PC, Laptop, home or car charger. LED battery status indicator.