The 62-144 is our basic Tone and Probe Kit which includes both the Amplifier Probe and Tone Generator units that can be used to identify or trace a cable by sending an analog tone signal on de-energized copper conductors from one end of a cable to the other. The amplifier probe is used to make the tone signal audible at the other end of the cable, or along the path of an exposed cable, allowing identification and location of the cable under tone. This kit includes the core features and functionality to trace cables for users who occasionally troubleshoot and locate cables and are looking for a cost-effective, easy-to-use basic unit. 9V batteries are included.