[High Quality] This Toner and Probe Kit is made of high-quality materials, resistant to wear and corrosion. The normal gain is 30 dB and the input impedance is nominally 100 M Ohm. Please note that the wire tracer requires two 9V batteries (not included). [Powerful Function] When used with any sound source, the professional wire probe and toner kit with adjustable volume can identify and trace wires or cables in a group without damaging the insulation. The clamp mode can be used for direct measurement of non-terminal cables, as well as for telephone and network line measurements. [Easy to Use] The method is simple and the test results are accurate. The insulation probes and built-in speakers can effectively avoid short circuits of the conductors. The measurement scope includes line tracking, short circuit testing, clear/busy/ringing identification, and safer use. [Safety and High Accuracy] The circuit tester has a spring-loaded ON/OFF button; adjustable volume sensitivity control; recessed terminal port for mobile phone connection; carbon fiber resistive plastic tip to prevent accidental short circuits when detecting wires. Optional continuous or adjustable generator, simple method and accurate test results. [Scope] The 200EP sound source and probe kit with probe are widely used in cable and wire maintenance. The measurement area includes line tracking, short circuit testing, clear/busy/ringing recognition. For non-terminal cables, the alligator clip mode can be used for direct measurement, telephone line and network cable measurement. Equipped with built-in speakers