The DigiPower Jumpstart JS1-IP2 Instant Cell Phone Charger provides instant power to iPhones and iPods with drained batteries. The world's smallest emergency charger readies your phone within minutes to make calls, providing an average of 2 bars of power/1 hour of talk time. The Jumpstart lithium battery connects to and hangs conveniently from your phone, is rechargeable up to 300 times, and holds its charge for a year. You can be reassured you will never be without cell phone power. The Jumpstart internal IC chip protects from over-charging and short-cirucits, while the LED charging indicators allow you to monitor your charging status.You can even recharge the Jumpstart and your cell phone simultaneously, using your cell phone's ac wall charger or 12V cigarette lighter adaptor.