Product details:

Sequential Battery Charging, LED Charging Indicators, Overheat and Short-Circuit Protection, 100-240 VAC Worldwide Use. Therefore once the first battery is fully charged it automatically switches to the second battery and starts the charging process over. The LEDs indicate what level your battery is at and the charger protects them from short-circuiting and instantly shuts off if the batteries are overheating. Because of the switching power between 100 to 240 VAC you are able to use the charger anywhere in the world. The DUO Charger is compatible with Nikon EN-EL18 EN-EL18a EN-EL18b and EN-EL18c type batteries and adapter plates are included so you can also charge EN-EL4 and EN-EL4a type batteries as well. Best Battery Chargers