Key FeaturesThis LAN Network Cable Tester is requisite and helpful in network/telephone installation and maintenance. It can judge wrong connection, short circuit and open circuit, offer you great help to keep your network work well. Features Test correspondingly double-twisted cables 1, 2, 3, 4, 5, 6, 7, 8 and ground Capable to judge wrong connection, short circuit and open circuit Cable tester for RJ11, RJ12, RJ45, Cat 5e, Cat 5, 10 / 100 Base-T, AT&T 258 A, TIA-568A / 568B .etc It can easily clarify cable, continuity, open and short Verifying cable continuity, open, short and cross wire pair up to 1000ft with remote kit 9 LED lights to indicated wiring connection on both remote and master unit Auto scanning function for rapid testing Grounding test Build in power switch for power saving Operate with one 9V battery (not included)