GARMIN 010-10635-00 Forerunner AC Charger. Every Garmin product is designed to meet the most demanding standard: customers satisfaction. That is why Garmin equipment is manufactured to give you reliable service for years to come, with intuitive features you can grow into over time - all at a price you can afford. This adapter plugs into any standard US 110VAC outlet to re-charge the Forerunner 301s internal lithium ion battery. The voltage range of the adapter is 110-240 VAC.