Milwaukee's M18 18-Volt Lithium-Ion XC Battery delivers more run time, power and speed than standard lithium-ion batteries to keep your tools powered longer. This 54-Watt hour REDLITHIUM battery is designed with superior pack construction, technology and performance to achieve optimal work per charge and work over pack life. With just this one versatile battery, you can power over 40 Milwaukee M18 cordless power tools, saving money and hassle for years to come.