This Pearstone Duo Battery Charger for Pentax D-Li90 conveniently charges two batteries simultaneously, drawing power from either an AC wall source (an AC cord with two-prong plug is included) or a 12/24V DC power source (a DC car charger is also included). Additionally, the Duo Charger features a USB power output to charge and power MP3 players, phones, digital cameras, and other devices with a USB power input.