Input: AC 100-240V Input voltage frequency: 50-60Hz. Output: 4.2V Current: 1000MA According to the tips, put 18730/18650/16730/16650 into the charger slot, the corresponding LED red light, indicating normal charging; when fully charged, red light is off, the green light, the battery is fully charged, it can be used. You can not reverse the battery to charge, if reverse please be corrected immediately to avoid accidents.