This device is for earth 2 or 3-wire AC or DC mains supplies up to 16amps and 250volts. Supplied with three sets of connecting cables: One for M3 at 16amps wire ended. One for M3 with IEC connections and the other unterminated for M1/M2 applications. Also supplied are the 46ZZ calibration adaptors with each CDN. The whole system is supplied with a ground plane complete with spring clips to grip the CDN and an appropriate earth lead. It arrives in a custom fitted case including user handbook.