Compatible with all Milwaukee M12 cordless tools and instruments, the M12 REDLITHIUM XC extended-capacity battery delivers 4 Ah (48-Watt hour) and 5 Ah of run time-even in sub-zero temperatures. Each 12-Volt lithium-ion battery is laden with new-age REDLINK circuitry engineered to prevent overloads and protect against cell-damaging discharge. Revolutionary cell monitoring and temperature regulation prolong this battery's operation and life expectancy, meaning fewer work interruptions and more recharges than ever. Professionals depend on heavy-duty, long-lasting performance and Milwaukee delivers with this 12-Volt battery pack.