The HiKOKI BSL1850Z is an 18v 5.0Ah Li-ion battery, fully compatible with the 18v Li-ion power tool range. The BSL1850Z offers up to 1,500 cycles rechargeable through Multiplex Protection Circuit that prevents over-load, over-charge and over-discharge. Full compatibility with Hitachis 18v slide Li-ion tools5.0Ah Li-ion Battery big power band up to 2 times longer runtime for the same weight3 way protection including deep discharge and overload protectionFast re-charge plus energy savingUp to 1,500 cycles rechargeable through multiplex protection circuit that prevents overload, overcharge and over discharge