Cable trackers are designed to identify and trace a group of wires or cables without damaging the insulation.This telephone cable tracing system consists of a tone generator and probe that allows you to find where the cable is routed and if (if it is) there is a break in the line. It also identifies the status of a working phone line, so you can determine if the line is free, ringing, or connected, all without any interference or damage to the cable installation. Advantages: Determine Cable or Wire Continuity Breakpoint Tracking and Traceback Diagnostics Send a single pure tone to the cable Learn the status of a free, calling or busy phone line Safely inspect cables without disrupting cable installations High quality tool with volume sensitivity control Read to use - just connect the battery and it's done Easy to install, commission and maintain one or more phone lines around your home or office with this high quality tracking system Specifications Single package size: 26 x 12.5 x 4 cm Power: 2 x 9V batteries (battery not supplied) Connector: RJ-11 (for phone jack) Includes: Transmitter, Receiver, Test Leads, Carrying Case and Instructions