Zircon MultiScanner i500 Center-Finding Stud Finder with Metal and AC Electrical Scanning and DVD How-To Guide Stud scan mode locates the center and edges of wood or metal studs up to 3/4-Inch (19-mm) deep and DeepScan mode doubles the scanning depth to 1-1/2-Inch (38-mm) deep Dedicated metal scan mode detects non-ferrous metal up to 1-1/2-Inch (38-mm) deep and ferrous metal up to 3-Inch (76-mm) deep Dedicated AC scan mode finds and traces live, unshielded electrical wiring up to 2-Inch (51-mm) deep Wire Warning detection indicates the presence of live, unshielded electrical wire up to 2 -Inch (51-mm) deep in stud and metal scan modes An ultra-bright LCD display screen clearly indicates the direction, edges and center of stud