Stitchway UltraPower 1900 mAh BLACK Backup Battery Charger for iPhone 4,4G, 3GS, 3G ,iPod, iTouch-EXTERNAL, PORTABLE, RECHARGEABLE Grade A Li-ion polymer cell and premium microchips create high-quality portable charger Portable yet powerful with 1900 mAh of juice; small form factor fits easily and unobtrusively onto your iPhone's 30-Pin connector Multiple protection system inside for big safety.It's designed for avoiding overcharge, overvoltage, overcurrent, over temperature and short circuit to ensure reliability and safety. *Please note: this is not compatible with newer Lightning connector phones*