JLERU Network LAN Ethernet Phone Telephone Cable Toner Wire Tracker Tracking System and Tester Trace telephone wire/LAN cable. Trace wire in electrical system. It can take place of cable teste Verify LAN cable condition. Continuity test. Cable Assignment Test and Cable State Testing (2-wire) Low Battery Indication with Bright white LED flash light. Rapidly find the target wire from among plenty of telephone wires. Rapidly find the target wire from among plenty of network wires. Find target wire on all types of connected operating Ethernet switch /Router/PC(No Battery)