GAOTek's line testers can perform both multiline and twisted pair testing. Moreover, these devices have specific functions that can detect high voltage and can also test whether there is high voltage on the line. These devices are designed to protect line installation or maintenance technicians from exposure to high voltage. The main key application of this devices is testing for insulation and tracing errors in the line. Technicians and engineers mainly use them to accurately install and maintain the telephone networks, as well as to identify the faults as poor insulation and breakage in the lines.

GAOTek's line testers are small, portable, and lightweight devices that have built-in systems with the latest technology such as mounted technology (SMT). These devices are used for testing the performance of telephone set, circuit functioning test, and security test which makes them ideal for identifying the defects in line.

The line testers are mainly used by engineers and ADSL technicians as the solution for line installation, inspection, testing, and maintenance of telecom networks.