How deep is the metal positioning rod positioned?

1 to 40 cm deep. It is used for short-distance precise positioning and security inspection. The handheld generic underground metal detector is 1 to 2M deep, and the small handheld metal detector is 1 to 40CM deep. It is used in outdoor treasure exploration, engineering exploration and other fields. Machines with synchronous multi-frequency technology can also look for gold and silver jewelry on high salinity beaches.