Black & Decker Compact Lithium Drill is powered by 7.2 volts Li-ion battery. This battery has the capacity to hold 80% of its charge for 90 days. You do not need to charge the unit before each use. It has a drilling capacity of up to 20mm in wood. Moreover, it is versatile in function as there is a forward and reverses switch available which enables you to tighten and loosen the surface easily. Its compact size allows you to reach the spaces where large drills can not reach. With that, various size diameters are available which include the following sizes 4mm, 5mm, 6mm, 8mm & 10mm.