the Tvr 10/100/1000 Tester Provides Everything You Need To Verify And Repair 10-, 100-, And 1000-mbps Copper Ethernet. The Main Unit That Performs Most Tests Such As Lan Device Type, Lan Speed, Duplex, And Poe. An Additional Probe Enables You To Locate Cables Or Switch Ports By Detecting A Tone Generated By The Handheld Tester. The Tester Enables You To Locate Faulty Switches, Pcs, Or Cable Connections That May Be Interfering With The Performance Of Your 10/100/1000base-t Network. You Can Even Go Inline Between Two Devices To Determine The Final Negotiated Speed And Duplex Of The Link. The Tvr 10/100/1000 Is Designed For Use By Installers And Repair People Who Are Documenting Legacy Lans, Installing And Repairing Lans, Or Expanding Existing Lans.