This charger will only work with single layer battery (such as Stock battery). It will not work with double layer extended battery. If you have a double layer extended battery, which has twice the thickness of the stock battery, this charger is not for you. ====================================================================== 100% Brand New. 1)AC/USB Desktop Battery Charger : * Quick charge with automatic constant current control prevents battery from over charging, short circuit, and electronic shock. * Charge your cell phone battery without the phone. * Also work with OEM (original) battery. * LED charging light indicator. Turn red in charging, turn blue when done. * Input: AC 100-240V 50/60Hz 150mAh. * Output: DC 4.2V 350mAh ± 50mA. * USB Port Output: 5.2V 800mAh. * Use this charger to charge the stock battery as well, swap one out when the other dies.