This smart charger can charge one to four IMR/Li-ion 18650 batteries simultaneously via wall AC power or 12V car power. It comes with the Gravity G1, G2 and G2X kits and is used to charge the 18650 batteries that are required to power the gimbals. Aside from 18650 batteries, the charger can also charge 26650, 22650, 18490, 18350, 17670, 17500, 16340, (RCR123), 14500, 10440 and Ni-MH/Ni-Cd: AA, AAA, AAAA, C batteries. Above each battery compartment is an LED indicator which indicates the amount of charge. Three solid LED bars over the battery indicates a full charge. Blinking LEDs indicate a still charging battery. The battery slots are spring loaded for optimum fit.