A wire tracker (or cable tracer) is a diagnostic tool designed for IT professionals and electricians to identify, trace, and test metallic cables, including RJ45 (Ethernet/LAN), RJ11 (telephone), and coaxial cables. It consists of a transmitter (emitter) that sends a tone signal and a receiver (probe) that detects that signal to locate the wire within a bundle or behind walls, without damaging the cable sheath.25