The HiKOKI UC18YSL3 charger is compatible with Li-Ion batteries. It is capable of charging 14.4V, 18V and 36v slide style batteries. It?s cooling feature helps to cool batteries during charging or before charging commences to prevent battery overheating ensuring extended battery life. This charger features preventative mechanism against charging a hot battery to extend battery life and a 3 way overcharge protection system to ensure battery is not overcharged. The two colour indicator light indicates what stage of charging the battery is in.Features3 way overcharge protection.Charging stage indicator light.Ideal for 14.4 and 18V batteries