This MilwaukeeA(R) 18 V Lithium-Ion battery works on the M18a,,c cordless tool system and has 3 Ah of run-time. This battery powers over 40 MilwaukeeA(R) M18a,,c cordless tools. Managed by Milwaukee's exclusive REDLINKa,,c intelligence, the battery features overload protection, a temperature management system, individual cell voltage monitoring, discharge protection and a battery fuel gauge.