Gomadic High Capacity Rechargeable External Battery Pack suitable for the Panasonic HC-V710 / V720 Integrated circuitry tailors output voltage and charging current to exact specification of the Panasonic HC-V710 / V720 (accurate to 0.1v). Specification: Internal Battery (7800mAh lithium polymer), Input port (microUSB), Output Port (Standard USB), Onboard Circuit Design (Panasonic HC-V710 / V720 Specific), Dimensions (2.75 X 3.25 X 0.75 inches), TipExchange enabled (Yes) Very easy to operate. Simply connect Panasonic HC-V710 / V720, press activation button on pack, and charging begins. Quick start guide included. Built using unique Gomadic TipExchange Technology that protects your investment by providing the ability to upgrade charging ports by simply swapping the physical connector. Built with high capacity lithium polymer rechargeable battery technology (28 Wh / 7800 mAh) in a compact design.