The Bosch GXS18V-23B21 18V Starter Kit delivers power in a compact size for light to standard applications. The 1.5 Ah SlimPack battery features 18V power in a lightweight frame. The battery weighs only 0.75 Lbs., which is ideal for professionals who do a great deal of work overhead or in tight spaces. Built with low-resistance Li-ion cells, the battery is efficient and delivers sufficient power. The battery is compatible with Bosch 18V Lithium-ion tools and chargers. The Bosch GAL18V-20 Lithium-ion charger is compatible with Bosch 18V Lithium-ion batteries. The battery and charger are not optimized for PROFACTOR™ high-power tools. Bosch's charging technology ensures a quick and efficient charge to get users back to work quickly. The charging indicator informs the user of the charging status of the battery.