NF816 Underground Cable Wire Locator Tracker Network Cable Tester Lan with Earphone The Underground Wire Locator is designed to locate the path of non-energized wires behind walls and underground Tracking underground, Buried Wires and other hidden-wires Locating Alarm, Sound & Computer Wires. Locating Hidden Receptacles Measuring Depth,Locating Circuit Breakers. Determining Which Receptacles are on Specific Circuits. Range-Up to 3 feet deep and 1000 feet in length