MultiScanner i520 OneStep quickly and easily locates the edges and center of wood and metal studs and joists behind walls floors and ceilings. It also locates metal as well as live AC electrical wiring. A 4-mode switch makes it easy to change functions while the ultra-bright display screen SpotLite Pointing System and audio tone all indicate the location of the target. The signal strength indicator helps to distinguish between shallow and deep targets. Stud Scan mode locates the edges and center of wood or metal studs up to 3/4" (19 mm) deep; DeepScan mode doubles the scanning depth to 1-1/2" (38 mm); An ultra-bright LCD screen indicates direction edges and center of studs; AC Scan finds and traces live unshielded electrical wiring up to 2" deep; Metal mode detects non-ferrous metal such as copper pipes up to 1-1/2" (38 mm) deep and ferrous metal such as rebar up to 3" (76 mm) deep; WireWarning detection indicates the presence of live unshielded electrical wire up to 2" (51 mm) deep in stud and metal scanning modes; ACT (Auto Correcting Technology) automatically corrects common user errors such as when scanning begins over a stud. Clamshell package.