modes, you can switch the mode between stud scan mode, metal scan mode and AC scan mode according to the object you want to detect. And the LCD icon will change according to the mode. Stud Scan Mode: Deep mode can test to a depth of 1.49inch (38mm), it is recommended to use the middle mode if the depth is less than 0.79inch (20mm) and the exact mode if the depth is less than 0.39inch (10mm). The stud mode detects direction (left and right), other modes do not have this feature. Metal Scan Mode: Mainly used to detect steel bars, metal keels, metal pipes, etc. in walls. The deepest depth tested was 2.36inch (60mm)(e.g. using 1/2inch rebar),If the signal is too b, it is recommended to set it to the middle mode or exact mode. AC Scan Mode: Mainly used to detect live (AC) wires in the wall. The deepest depth of the uncovered wire is 2inch (51mm). If the signal is too b, it is recommended to adjust it to the middle mode or exact mode. Easy to Use: Move the tester on the desired surface to detect for STUDS, metal, rebar, pipes, AC wire, etc., you can scan the object from left to right. The level part can be picked up separately to measure the horizontal position. And with magnetic to collect the metal nails. Wide Applications: Multi-scene applications, whether industrial and domestic use, can easily cope with. Suitable for home decoration and renovation, wall decoration installation, appliance installation and maintenance, etc. Specifications: Name: Wall Metal Detector Material: ABS Battery: 1 * built-in 9V 6F22 battery (included) Auto power off time: about 150s Operating temperature: 0-50/32-122 Storage temperature: -10 to 60/14-140 Operating humidity: 35-55%Rh Package size: 216 * 81 * 44mm / 8.50 * 3.19 * 1.73in Package weight: 280g / 9.88ounce Packing List: 1 * Wall Metal Detector