StarTech.com's Advanced Network Cable Tester (RJ45) lets you test several long network cables faster and more efficiently than ever before._x000D_ The network cable tester uses remote loop-back plugs, each with their own unique, easy-to-identify ID number. If several cables need to be tested, users can put a loop-back plug on the end of each cable run and go to the other end to test and identify each one._x000D_ The network cable tester provides a basic continuity test with a pin-map that will identify wiring errors, allowing them to be quickly corrected. The cable tester also identifies several common pinnings and displays the applications for each._x000D_ Please note: the Network Cable Tester requires a separate 9V battery (not included) to operate.