This long-lasting Garmin rechargeable battery pack is more convenient and easier than choosing two AA batteries. The NiMH battery can be charged by your compatible outdoor handheld device — simply charge your device using an AC adapter or the USB cable on your computer and your battery pack will be back to full charge for extended use. This is compatible with the Astro 430, GPSMAP 64/64s/64st & Oregon 600/600t/650/650t/700/750/750t