The Nitecore D4 is a universal smart charger compatible with almost all cylindrical rechargeable batteries, thus eliminating the need to own several chargers. The D4 automatically detects Li-ion, Ni-MH and Ni-Cd batteries, and through manual selection is also capable of charging LiFePO4 batteries. Intelligent charging circuitry selects the optimal charging mode (CC, CV and dV/dt) for a given battery and each of the D4's four microcomputer-controlled charging slots then monitors and charges the battery independently. Furthermore, an integrated digital LCD screen clearly displays charging progress, voltage, current and time while an intelligent automatic power-off function terminates current when charging is complete. The Nitecore D4: The world's most advanced fully-automatic digital charger. It's as simple as insert, detect and charge.