Sienoc Patch Cable Tester RJ45 CAT5 CAT6 Cat7 RJ11 RJ12 LAN ISDN DSL Network Testing Device Portable size: approx 105 x 100 x 25mm  Test double-twisted cables 1, 2, 3, 4, 5, 6, 7, 8 and Ground  Can judge wrong connection, short circuit and open circuit. Cable Tester for RJ11, RJ12, RJ45, TIA-568A/568B .etc  9 LED lights to indicated wiring connection on both remote and master unit  Auto scanning function for rapid testing. Grounding Test  Slow automatic grade and Manual mode  Build in power switch for power saving  Operate with one 9V battery ( Not Included )