Professional tool for commercial or occasional use. -This instrument is designed to identify and trace wires or cables without damaging the insulation. -Also used for checking short circuit and locating open circuits etc... -There is a sender and a receiver included in this instrument. -Tracing of wires is made possible even inside bundles, conduits, behind panels, under carpets, upholstery etc... -Simple to use simply connect the transmitter in series with the circuit or wire under test and then scan the circuit / wire with the tracers flexible probe to find the trouble spot. -Only for use on DC voltage do not use on AC voltage. -Operates on DC voltages from 6 42 volts -Do not connect to circuit exceeding 42 volts DC. -Do not use with any component or circuits of the ignition system. -Internally protected against power surges and overloads -Adjustable sensitivity for all tracing situations -The probe of the receiver is built of coiled steel and may be bent as needed in order to reach wires in congested or difficult areas. -For the best possible range the receivers probe tip (black cap) should be positioned perpendicular (90 degrees) to the wire being traced. -7" flexible probe allows reaching wires in congested places -Transmitter and receiver LEDS show open or short circuit conditions -Adjustable sensitivity for all tracing situations -Runs off 2 x 9v batteries (included) -Comes complete with a full set of instructions for accurate and quick use -Comes in a pouch for easy storage and transportation.