The Milwaukee M18 REDLITHIUM XC5.0 Starter Kit delivers up to 2.5X more runtime， 20% more power and 2X more recharges than its competition. The lithium-ion battery pack has superior pack construction， electronics， and performance delivering more work per charge and more work over pack life than any battery on the market. The rechargeable battery delivers 5.0 amp-hours of runtime. Each battery pack is durably built for heavy-duty use， runs cooler， and performs in climates below 0°F/-18°C. This protection routes water away from the electronics and out of the battery pack， extends battery run-time and life by minimizing heat， and prevents pack failures from vibration or drops. Built-in Redlink Intelligence protects the battery from overloads， preventing power tool damage in heavy-duty situations， while the discharge protection prevents cell damage. An integrated temperature management system and individual cell monitoring help to maximize battery life. Switch to Milwaukee's REDLITHIUM XC5.0 Battery Pack to instantly upgrade the runtime and durability of Milwaukee M18 cordless tools.