BRAND NEW ONE+ 18V Lithium-Ion HIGH PERFORMANCE Starter Kit with 2.0 Ah Battery, (2) 4.0 Ah Batteries, and Charger Extend your productivity with up to 4X more runtime INTELLICELL battery technology features advanced electronics allowing batteries to last longer, think smarter and deliver up to 30% more power COOL-CORE design reduces temperature while in-use to optimize battery performance and extended battery life Advanced lithium cells maximize performance and runtime during demanding applications High visibility LED fuel gauge clearly indicates remaining runtime Easily snaps into place and detaches with quick-release buttons Pair with 18V ONE+ tools for optimized performance Recharge on any 18V ONE+ charger