The Milwaukee M18 18V Lithium-Ion REDLITHIUM FORGE XC 8.0 Ah Battery Pack is a high-performance battery designed for demanding applications. It delivers 8 amp hours of runtime with the power equivalent to the M18 REDLITHIUM HIGH OUTPUT HD12.0 but in a more compact and lighter design. Featuring the COOL-CYCLE Active Cooling System, this battery offers high-speed cooling for reduced downtime. With a 35-minute supercharge to 80% using compatible chargers, such as the M18 Dual Bay Simultaneous Super Charger, this battery ensures minimal interruptions, keeping you productive on the job.