The RYOBI 18V ONE+ Lithium Starter Kit is the perfect way to extend the runtime of your 18V system and increase your productivity. Add a 4Ah and 2Ah Lithium battery and charger to your collection when you purchase this starter kit. With up to 3X more runtime than the standard lithium battery, you will get more done, faster. The compact design is lighter weight and reduces overall user fatigue. These batteries feature a high visibility LED fuel gauge to clearly indicate remaining runtime.