Put an end to tiresome searching for the right wire since the ct 20 has an additional remote unit you can do without identification of an additional person cable even if these are moved in different areas apart from the allocation of the cable even the correct polarity can be determined the ct 20 can also be used as a standard continuity tester the display take place on the ct 20 acoustically and optically as well as with the remote unit over a two coloured led the professional tester is v