Mophie has introduced its new Juice Pack for the iPhone 3G. Like the company’s Juice Packs for iPhone and iPod touch, the iPhone 3G version houses a rechargeable lithium polymer battery within a soft touch, non-slip rear case. According to Mophie, the Juice Pack offers an additional 350 hours of standby time, 6 hours of talk time on 3G, 12 hours of talk time on 2G, 6 hours of Internet use on 3G, 8 hours of video playback, or 28 hours of audio playback. Other features include “Works With iPhone” certification, a 4 LED charge status indicator, and a USB passthrough port for charging and syncing. The Mophie Juice Pack for iPhone 3G is available for pre-order now and will ship in September for $100.