The MILWAUKEE® M18™ REDLITHIUM™ FORGE™ XC8.0 Starter Kit delivers HIGH OUTPUT™ 12.0 power in a smaller size and the longest life vs REDLITHIUM™ batteries. REDLITHIUM™ FORGE™ are Milwaukee's most powerful, fastest charging, and longest life batteries. The REDLTIHIUM™ FORGE™ XC8.0 delivers 8 amp hours of runtime, but with the same power as the M18™ REDLITHIUM™ HIGH OUTPUT™ HD12.0 in a smaller size and lighter weight design. The lithium-ion battery has the longest life, most recharges, and best performance over the life of the battery