Gomadic Portable AA Battery Pack designed for the Garmin Nuvi 650 - Powered by 4 X AA Batteries to provide Emergency charge. Built using TipExchange Technology Integrated circuitry regulates output voltage specific to the Garmin Nuvi 650. Advanced logic maximizes overall charger efficiency. Built using the unique Gomadic TipExchange Technology that protects your investment by providing the ability to upgrade charging ports by simply swapping physical connectors. Specification: Input Voltage (4 X AA Batteries), Cable length (6 inches), Dimensions (5.0 X 1.5 X 0.75 inches), Circuit Design (Garmin Nuvi 650 specific), TipExchange enabled (Yes) Internal circuit designed to protect your Garmin Nuvi 650 from power surges, overcharging and short circuiting. Safely engineered with reverse polarity protection, in the event batteries are accidentally put in incorrectly.