Includes: 1 Fat Pack Battery And ChargerVoltage: 18Amperage: 4.0AhBattery Chemistry: Lithium IonFlexible Power System (FPS) Works With All Bosch 18V Lithium-Ion ToolsMaximum Run Time Up To 65% More Run Time Compared To Bosch 3Ah BatteriesUnique CoolPack Design Keeps Battery Cooler, Lasts Up To 2x LongerIntegrated Fuel Gauge For Fast And Easy Charge StatusCold Weather Operation, Battery Will Work Down To -4 Degrees FahrenheitDurable Housing Survives A 3 Meter Drop