This charger is designed specifically for use with our KXBT2 Li-ion battery pack. It can safely charge the KXBT2 in 1 to 3 hours. Note: To charge the battery, you must first remove it as described in the KX2 owner’s manual. It cannot be charged while inside the radio. The power jack on the left side panel is isolated from the internal power jack, and cannot supply power to the battery.