Gomadic High Capacity Rechargeable External Battery Pack suitable for the Panasonic HDC-TM90 Camcorder Very easy to operate. Simply connect Panasonic HDC-TM90 Camcorder, press activation button on pack, and charging begins. Quick start guide included. Specification: Internal Battery (7800mAh lithium polymer), Input port (microUSB), Output Port (Standard USB), Onboard Circuit Design (Panasonic HDC-TM90 Camcorder Specific), Dimensions (2.75 X 3.25 X 0.75 inches), TipExchange enabled (Yes) Integrated circuitry tailors output voltage and charging current to exact specification of the Panasonic HDC-TM90 Camcorder (accurate to 0.1v). Continue to use your Panasonic HDC-TM90 Camcorder for hours OR recharge it on the go without being tethered to a wall outlet Built using unique Gomadic TipExchange Technology that protects your investment by providing the ability to upgrade charging ports by simply swapping the physical connector.