ABOUT DETAILS - The gain is norminal 30dB, the input impedance is nominal 100M Ohm, and please notice that wire tracer needs one 9V Battery(NOT INCLUDED).MEASURING RANGE - Measurement categories include line tracking, short circuit testing, clear/busy/ringing identification. Selectable continuous or variable tone generatorCLAMP MODE - For non-terminal cables, clamp mode can be used for direct measurement, as well as for telephone and network line measurement.HIGH ACCURACY - With optional continuous or adjustable generator, the is simple and the test results are accurate.AVOID SHORT CIRCUIT - Built-in speaker tube on the probe, insulation probe and built-in loudspeaker can effectively avoid short circuit of conductor and to use.Colour:Gray-WhiteMaterial:Plastic + MetalPackage Contents:1x wire tracer1x connector1x accessories1x canvas bag1x English manualOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.