When you need something that packs a punch to get through brick and stone walls, a hammer drill delivers. This powerful tool is perfect for heavy-duty jobs such as hanging TVs, replacing guttering and feeding cable into properties from outside. The best drills give you the choice of speeds and drill types. The bit punches and spins at the same time — smashing its way through hard surfaces without sacrificing accuracy. Special features to look out for include keyless chuck, variable speed control, speed preselection and an overload clutch.