1[Position Detection] The wall scanner can detect the depth and position of metal, wood and live circuits in wall separately, suitable for interior structures.2[Double Alert] When the wall scanner senses metal, wood and live circuits, it will have an analogue bar display and an audible alert for convenience and practicality.3[Principle Of Operation] Designed using the principle that changes in the strength of the material below the surface of the object being measured cause a change in the frequency of the detector.4[Wide Application] Wall detector can test metal, wood and live circuits separately, with a maximum detection depth below the surface of a uniform object.5[Wear Resistant And Durable] The digital wire finder is made of ABS material, which is durable, wear resistant and not easy to break. Compact size, easy to carry.