This tone generator and probe are Practical Tools. They apply for Installing Network and Checking Objects. The tone generator emits a single signal or multiple frequency signals and has Two Single Test Cartridges and a 4 P Test Joint. When wires are bounded and hidden in the wall or are imbedded by a Barrier who you are using the tone generator, the tone signal which is set by the main program is very easy to test with the program. The continuity of a wire, a fault of the Wire, the Polarity of the Circuit, A Network or the Working Voltage of the Modular Cable Can Be Tested by This Group Tester. The amplifier probe is designed to identify and trace wires or cables with a group with the Damaging of Insulation Works with Any Tone Generator to Identify Wires Volume Control Environment Recessed on/Off Button Prevents Battery Drain It Can Be Power With Only One 9V Battery and the Device Has a Long Battery Life (Approx. 100 Hours of Use) a Plug Recepta Plug A 3-Position Toggle Switch Controls the Modes of Operation Plus a 3-Colored LED is provides for the line polarity, Continuity and Voltage Testing a Tone Selector Switch, Located Inside the Test Set is Proveded or dual Alternating Tone (Caution: Do'nt connect to an Active Ac Circuit Exceeding 24V in this mode)