This model IMP880 is sold and marketed exclusively by imaxpower. Up to 50 hours non-stop 3Gs 3G iPhone movie playing time, 600% extra iphone battery life. The most powerful 3G 3Gs iPhone iTouch External Backup Li-ion battery pack in the whole USA market. It will extend your 3G 3Gs iPhone iTouch movie time up to 50 hours with total 600% of 3G 3Gs iPhone battery life! Its capacity is 8800 mAh at 5V output voltage. It can be directly charged with high speed imaxpower AC charger. IMP880 can power up your mobile device through an USB cable. This battery pack is light in weight (250g) and environmental safe. Key benefits for the Li-ion battery pack IMP880· Boost 3G 3Gs iPhone video play time up to 50 hours (with speaker on) ·Total 600% of 3G 3Gs iPhone battery, light weight 250g ·Boost 3Gs iPhone internet time to 50 hours, audio time up to 250 hours ·It can power all the latest 8G, 16G 3G and 3Gs iPhone, 8G,16G 1st 2nd and 3rd generation itouch, all the latest ipod video classic 30GB & 60GB & 80GB & ipod nano 2GB & 4GB with 3Gs iPhone connector ·It can also power the major brand cell phone like blackberry phone (curve, tour, bold and storm) with correct adapters, Nintendo DS and Gameboy with correct adopters. A Free imaxpower AC charger is included. 6 months warranty is included