Compatible With All M18 Power Tools Fuel gauge onboard: Displays remaining runtime. Fully compatible with the M18 system, featuring over 200+ tools. 1.5 Ah of run time Lithium-ion battery for longevity and fade-free power. Equivalent run time with 40% less weight than an 18-Volt NiCd battery. Onboard fuel gauge that shows the remaining run time, enabling you to adequately prepare for projects and have less downtime on the job. REDLINK intelligence overload protection that prevents you from accidentally damaging your tools during heavy duty applications. Temperature management system to keep the battery in an ideal range, helping extend its life Individual cell monitoring that ensures optimal charge and discharge. Compact, lightweight design that fits into tight workspaces and reduces user fatigue. All-weather performance that gives fade-free power in extreme job site conditions. Charger sold separately Compatible with all M18 chargers. Up to 40% more run-time. Redlink intelligence: provides optimized performance and overload protection using total system communication between tool, battery and charger. All-weather performance: delivers fade-free power in extreme jobsite conditions.