The Authentic Nitecore D2 battery charger works with cylindrical rechargeable batteries of various sizes. The battery charger is capable of detecting Li-ion, Li-FEPO4, Ni-MH, and Ni-Cd batteries automatically. It has two microcomputer-controlled slots to charge two batteries simultaneously, and also monitor them independently. The charger has an LCD panel to display details about the progress and parameters related to charging. The Nitecore brand charger detects the battery power status automatically and selects the charge mode and voltage appropriately. The two side buttons allow users to select these values based on your preferences. The durable ABS charger is flame resistant and retardant. It has an optimal charge design for IMR batteries and features optimal heat dissipation. It offers protection against reverse polarity, short circuit, and over voltage, charging, and discharging. The indicator on the charger stops blinking when the battery is fully charged. The charger comes with a US plug and works at a voltage of 100 to 240 VAC or 12 VDC.