The M12 Battery Charger quickly charges all M12 batteries. It allows you to monitor charging progress, communicates directly with the battery pack to manage charges, and features an easy-to-load design. Its slim profile requires little bench-top room, while the pass-through plug conserves valuable outlet space. The Milwaukee M12 REDLITHIUM battery is smaller and lighter than NiCad compact batteries, yet delivers long runtime and fade-free power. The battery is designed with superior pack construction, electronics, and performance, to optimize work per charge and work over pack life on the jobsite. Managed by Milwaukee's exclusive REDLINK Intelligence, the battery features overload protection to prevent you from damaging your cordless power tools in heavy-duty situations, while the discharge protection prevents cell damage. The temperature management system and individual cell monitoring help maximize battery life. Use this durable battery to power your Milwaukee M12 cordless power tools.