Gomadic Intelligent Compact Car / Auto DC Charger suitable for the Garmin Forerunner 305 - 2A / 10W power at half the size. Uses Gomadic TipExchange Technology Gomadic TipExchange Technology protects your investment by providing a means to change/upgrade your charger by simply swapping the physical charging tip. (Charging tip for Garmin Forerunner 305) included with additional tips sold separately) Intelligent circuit provides precise output voltage and resistor configuration specific to the Garmin Forerunner 305. This ensures battery is safely and efficiently charged without affecting battery longevity. Charger provides a full 10W (2,000mAh) of available current in a small form factor a little over 1 inch long. Flexible, straight cable measure 50 inches in total length. Generous input voltage range of 12-24VDC, supports a wide variety of DC charging ports from cars and trucks (both foreign and domestic) to boats, planes and RVs. Built using high quality capacitors and circuit components to ensure that charging current does not interfere with FM radio transmissions. Rigorous Q&A process.