No damage insulation layer: The cable finder detects the passage of cables or wires without damaging the insulation..Check if the cable is continuous..Trace the cables or wires and diagnose the points of & 39;stopCheck network cable and line function: receive audio signals via cables or wires (telephone lines)..Identify working phone line status (idle, ringing, lifting)..Send signal single or two-tone cableor target cable.Easy to carry: Small, light, easy to carry, long service life, low power consumption, compact and safe. It can be reused and is durable. Comes with a bag that can be stored well and prevents dust and collisions.Mulit-Function: Voltage Detector can also diagnose break point, receive tone signal on cables or wires (telephone line)