The MILWAUKEE M18 REDLITHIUM XC5.0 Resistant Battery is built with a resistant housing, providing increased protection against exposure to common oils, greases, and solvents found in transportation maintenance and manufacturing environments. The Milwaukee M18 REDLITHIUM XC5.0 Resistant Battery delivers the same best-in-class performance as the standard Milwaukee M18 REDLITHIUM XC5.0 battery with 2.5X more runtime and 20% more power than the standard lithium-ion batteries. Each battery pack is durably built for heavy-duty use, runs cooler, and performs in cold weather climates. Built-in REDLINK Intelligence protects the battery from overloads, preventing you from damaging your cordless power tools in heavy-duty situations, while the discharge protection prevents cell damage. An integrated temperature management system and individual cell monitoring help to maximize your battery's life. The M18 REDLITHIUM XC5.0 Resistant battery is fully compatible with all 250+ MILWAUKEE M18 solutions. In addition to these batteries, this starter kit includes the M18 & M12 Battery Charger and contractor bag.