This RJ11 RJ45 Network telephone cable tracking system can find wires on all types of connected operating Ethernet switch/router/PC terminal. The cable tester comes with a 3.5mm earphone that allows you to hear tone clearly in noisy environments. This Cable Tester can also detect the status of a working network or telephone wire. Both emitter & receiver with thumbwheel allows you to select desired toning mode. The 8-level led indicators indicates signal strength & wire connectivity. The receiver has both sound & LED signal indicators. By comparing the volume of the “tout” sound, you can find the target wire with the highest volume. This Phone Network Cable Tester Comes with a Full Year !! Features: Emitter/receiver with thumbwheel 8-level LED indicators Collation function Open or short circuits testing functions Trace telephone /LAN wire Electric wire finding function DC level testing function Low voltage alarm function Receiver with built-in speaker & LED indicator Headset Function Can test the continuity of cables or wires Tracks & diagnoses breakpoints Reports line status without ringing or turning on Come with a lanyard Comes with a carrying bag Specifications: Product: Multi-Function Cable Tracker Interface: Insulated Crocodile Test clips & RJ-11 (for telephone jack) Power: Via DC 9V Battery Built-In Speaker: Yes LED Indicator: Yes Headphone Jack: Yes 3.5mm Usage: for telephone, network and electric wires Emitter Size: ( L x W x H ): 14o x 75 × 30mm Receiver Size: ( L x W x H): 220 × 48 × 32mm weight : 400g Package Includes: 1 x Emitter 1 x Receiver 1 x Earphone 1 x RJ11 Telephone Cable 1 x Cable with crocodile clamps 1 x RJ45 Network Cable 2 x Lanyards 1 x Carrying Bag 1 x User Manual 1 x Retail Box