uNu Exera Battery Case & Duo Charging Dock for iPhone 4 & 4S - Black

The Exera Battery Case features a swappable 1700mah battery module, a removable battery housing, an interchangable slim backcover, and a bumper with a great selection of different colors By using the two integrated Exera battery ports users can connect and charge Exera batteries directly to the hub, eliminating the need for a phone-charging cable. Plus, swapping depleted batteries with fully-charged batteries from the hub allows for a constantly replenished source of battery power. This comprehensive hub is equipped with two Exera battery ports and an additional USB outlet allowing for up to three devices to simultaneously connect. By charging multiple batteries at once uNu has eliminated constantly swapping charged and un-charged batteries. Charge up to 3 batteries at once! Via the USB port and two Exera battery ports users can charge an iPhone 4/4S and battery case, plus two additional Exera batteries. In a single charging session users have access to a possible 4 charged batteries (integrated iPhone battery, and three Exera batteries) The Exera system includes a fully-customizable iPhone 4/4S battery case which practically doubles battery life, plus the newly released Exera Charger Duo Charging Dock which includes a multi-port hub and two additional batteries which are compatible with the Exera Battery Case, for continuous, wireless, battery charging. Made for peace-of-mind, the newly released Duo Charging Dock adds an unlimited power source to complement the Exera Battery Case. Featuring dual slots for the Exera batteries and a USB port the Duo Charging Dock can completely charge two batteries and the external battery case in one night, or allow consumers to swap batteries at their convenience creating a continuously replenishing power source. In all, the Exera System comes complete with an Exera Battery Case, mini-USB charging cable, three Exera batteries, and the Exera Charger Duo Charging Dock.