ABOUT DETAILS - The gain is nominal 30dB, the input impedance is nominal 100M Ohm. Please note that the wire tracer requires one 9V battery (not included). MEASURING RANGE - Measurement categories include line tracking, short circuit testing, and clear/busy/ringing identification. Features selectable continuous or variable tone generator. CLAMP MODE - For non-terminal cables, clamp mode allows direct measurement and can be used for telephone and network line testing. HIGH ACCURACY - With optional continuous or adjustable tone generator, the operation is simple and test results are accurate. AVOID SHORT CIRCUIT - Built-in speaker tube on the probe, insulated probe tip, and internal loudspeaker help prevent conductor short circuits. Color: Gray-White Material: Plastic + Metal Package Contents: 1 x Wire Tracer, 1 x Connector, 1 x Accessories, 1 x Canvas Bag, 1 x English Manual Note: Only the items listed above are included. Other products are not included. Note: Lighting and display differences may cause slight color variations between the image and the actual item. Measurement error allowance is +/- 1-3 cm.