"This tester features built in functions for analog tracing, cable mapping, POE voltage measuring, digital tracing with adjustable sensitivity,cable length measuring, and many more functions. Its long-tracing distances, rapid and precise cable length measuring,and strong audible signal make it a powerful tool to have at your disposal.It's the perfect tool for laboratories, factories, radio lovers, network installers, technicians and more. Wire Tracking: Advanced tracking allows you to quickly identify the required line pairs among large bundles.Featuring capabilities for tracking network cables such as RJ45, RJ11, and many more. Network Cable Collation: Features built in functions for testing the connection status of network cables such as open circuit,shorted connections, miswired and reversed connections, and more. Allowing you to track cables and wires and identify the breaking point. Continuity Checking: Automatically scans for miswiring and cable order as well as open and shorted circuits.Allowing you to detect the continuity of cables and wires without damaging the insulation. Checking The Line Order Of Network Cables: When using crystal head connectors the line finder allows you to test the function of network cables before installing them. Telephone Line Status Testing: Features a built in status checker for any working telephone lines (clear, ring, busy) and remote ID Mapping (Adapter required). Non-contact Voltage Detecting: The receiver of this unit can be used to detect the AC voltage of standard electrical wiring with both safety and accuracy.