Stud scan mode locates the edges and centre of wood or metal studs up to 3/4 in. (19 mm) deep DeepScan mode doubles the scanning depth to 1-1/2 in. (38 mm) Metal scan locates non-ferrous metal, such as copper pipe, up to 1-1/2 in. (38 mm) deep and ferrous WireWarning detection indicates the presence of live, unshielded AC electrical wire up to 2 in. (51 ACT (Auto Correcting Technology) automatically corrects common user errors, such as when scanning beMultiScanner HD800 quickly and easily locates the edges and centre of wood and metal studs and joists behind walls, floors, and ceilings. It also locates metal targets up to 3 in. (76 mm) deep. A 3-mode switch makes it easy to change functions, while the display screen, SpotLite Pointer, and audio tone all indicate the location of the target. The signal strength indicator helps to distinguish between shallow and deep targets.