StudScan mode locates the edges and center of wood or metal studs up to 19 mm deep DeepScan® mode doubles the scanning depth to 38 mm AC Scan mode locates live, unshielded electrical wire up to 51 mm deep. Metal Scan mode locates ferrous metal, such as rebar, up to 76 mm deep WireWarning® Detection indicates the presence of live, unshielded electrical wiring up to 51 mm deep ACT™ (Auto Correcting Technology) automatically corrects common user errors, such as when scanning begins over a stud