Power when and where you need it.At the same time you're charging the internal battery of your iPod or iPhone, PowerBlock Reserve is also charging the detachable Reserve battery pack for your iPod or iPhone. It's like getting twice as much use out of every time you charge.PowerBlock is our best-selling AC charger/adapter for USB-rechargeable devices, including iPod, iPhone, and other phones and MP3 players. PowerBlock works in almost any 100 to 240 volt AC wall outlet, and delivers safe power levels for iPod, iPhone, MP3 players, and other USB devices. Take the detachable battery pack with you (it's small enough to fit in your jeans watch pocket). The Reserve battery snaps into the Dock Connector of your iPod or iPhone, adding hours of additional use. No more worrying about battery life; no need to lug your charger along with you.PowerBlock Reserve is the most USB charge you can pack into the smallest footprint.The Reserve battery works with dock connector iPod models. Due to the placement of the dock connector, the headphone jack of iPod touch and iPod nano is unavailable while charging with detachable Reserve battery.FeaturesThe industry's most trusted AC chargerCharges iPhone, iPod, MP3 players, other USB-chargeable devicesRemovable backup battery provides hours of additional use for iPhone and iPod