A reversible drill can alter its rotations from a clockwise direction to a counter clockwise direction, a feature that makes it suitable for both drilling and driving.
A hammer drill contains a hammer clutch or a hammer-like mechanism which provides a circular rotation and a forward driving force. A hammer drill is capable of performing heavy-duty tasks, but it can also be used as a regular power drill.
The height represents the vertical dimension of the product. We consider a smaller height better because it assures easy maneuverability.
Drills with LED light provide a constant light source.
We consider a lower weight better because lighter devices are more comfortable to carry. A lower weight is also an advantage for home appliances, as it makes transportation easier, and for many other types of products.
The width represents the horizontal dimension of the product. We consider a smaller width better because it assures easy maneuverability.