1. Wide detection area - The maximum detection area of metal parts is 3 inches (3 inches), bolts 5 cm (2 inches). Just find the center and edges, precisely locates metal tubes, live wire studs, wooden frames, hidden beams behind walls, floors or ceilings. 2. Find Center: AC wire warning flag will show on LCD when live wires are monitored. Three detection modes indicate the intensity, the closeness of the wooden studs, the center, the highest column is the center, and the Studs beep will remind you when you have reached the destination. 3. Calibration - Before detection, please hold the scan button for 1-2 seconds. and it is calibrated. The beep sound will remind you when you have finished your work. You may need to recalibrate your device if the button was accidentally unlocked at first, or you think it is necessary during the process. 4. Excellent Screen Backlight - LCD backlight provides a clear look even in low light conditions and displays detection mode. When the battery is low, the audio display reminds you with a beep sound. Number of pieces delivered: 1 Color: black yellow Size: 75*38*167mm Specification: 1) Quickly detect the center position of the rod 2) LCD display, easy to read 3) Wood metal rods detectable with lower wall thickness to 1 1/2 inches (38 mm) 4) Detectable metal pipes with wall thickness less than 2.36 inches (60 mm) 5) Detects live wires in walls up to 2 inches (51mm) thick 6) All detection functions have auto-correction function 7) Without battery (6F22 9V)