Newcomdigi Multiscanner, Stud Finder, Metal Detection and Live AC Wire Tracing 3 In 1 Sensor Multifunction Detector, Digital Scanning 3-IN-1 MODES: The Stud finder, or stud sensor adopt the recent sensor technology, works great for detecting stud in drywall. Besides, it still comes with other features: LOCATE METAL and LIVE AC WIRES. HOW TO USE: Calibration First, (do it again whenever it seems to be inconsistent) start out in an 100% no stud area, and slowly move until a stud is find, and then the second, put your mark of the 2 and try to drill. Be PATIENTduring the process. WHEN DETECTS AN OBJECT: the spotlight appears and mark in the groove position. Sound Signal Reminder: It will remind you with sound signal when it detects wall studs, metal pipes and electrical wires. MORE EFFECTIVE STUD FINDER: Large LCD screen, easy to read and with smart audible indicating function when the stud,metal or wires is detected.(BEEP). 100% SATISFACTION OR MONEY BACK GUARANTEE: Just contact us if you are not satisfied for any reason and we will replace it or issue you a full refund.