The Check-All also comes with built-in tone generator to allow users to quickly trace wiring using tone probes. The secondary "twin” unit is designed to provide the same function as the main unit as it offers the same LED display to provide the same result as the main unit, and it also has its own pair of TX / RX ports to conduct testing on its own. Features: • Test RJ45 (8P8C) as well as RJ48 (10P10C) cables • Provides pin-by-pin configuration of 1-10 pin cables • Traces cable / network por