Fangrui Product Details The Tone Generator And Probe Kit Is Made Of High-quality Materials, Wear-resistant, Corrosion-resistant, Small In Overall Weight, And Easy To Carry. The Gain Is Normal 30db, Input Impedance Is Nominal 100m Ohm, 200ep Inductive Amplifier. Note:the Wire Tracker Needs Two 9v Batteries(not Included) 200ep Tone Generator Wire Tracer With Probe Are Widely Used In The Maintenance Of Cables And Wires. The Measurement Area Includes Line Tracking, Short Circuit Test, Clear/busy/ringing Identification. Insulation Probe And Built-in Loudspeaker Can Effectively Avoid Short Circuits Of Conductor And Make The Network Toner And Probe Kit Safer To Use, Essential Tool For Electricians When Used With Any Tone Generator, The Professional Wire Toner Probe Kit Has Adjustable Volume For Identifying And Tracking Wires Or Cables Within A Group Without Destroying Insulation! For Non-terminated Cables, The Clamping Method Can Be Used For Direct Measurements As Well As For Telephone And Network Line Measurements Electric Circuit Tr