Detectors are effective tools for finding objects in difficult conditions. These objects are usually hidden beneath the surface of walls. Usually they include Cables, Pipes and even materials made of Steel and Wood. Detectors are also known as Wall Scanners. With the help of these tools you can do reliable detection even of deep lying objects. Detectors can be find in various models. Usually they are multi-functional and can sense more than one material. But there are some other models as well. Simple models of detectors are used for detecting cable and they are also known as voltage detectors. Stud (Studs are frames made of wood or metal within wall that support doors ,windows, etc.) Detectors are very strong and sense areas of greater density. Beside metal , they can detect wood too.