... , CAT5e, 10/100BaseT, TIA-568A/568B, AT&T 258-A RJ45 Network Cable Tester test correspondingly double-twisted cables 1, 2, 3 ... connection on both remote and master unit With this RJ12 Network Cable Tester, you can judge wrong connection, short circuit and ... 9V battery (not included) Comes with a leather carrying case Compact and light weight RJ11 Network Cable Tester, very practical for home ...