The Authentic Nitecore D4 battery charger is a smart charger that is compatible with Li-ion, Ni-Cd, and Ni-MH rechargeable batteries of many sizes. This eliminates the need to own multiple chargers for different batteries. The charger can also be manually set to charge LiFePO4 batteries. It's four micro-computer controlled charging slots charge four batteries at a time while monitoring each battery independently. The charger has a US type plug and an integrated LCD screen that gives details about the voltage, current, the time required to charge and charging progress. The automatic power-off function stops the current flow when the charging process is complete. The unit has an optimized charging design for IMR batteries. There are two buttons on the side to choose the battery type and charging parameters. The indicator present in the charger turns green when the battery is fully charged. The ABS charger is flame resistant and retardant, as well as features over-charge prevention, temperature monitoring and reverse polarity protection. It operates at an input voltage of 100 to 240 volts at a frequency of 50/60 Hz.