To connect safely 4 mm banana leads to CEE 3P+N+E+pilot 6h 415-volt 63-ampere power sockets. To convert CEE 3P+N+E+pilot 6h 415-volt 63-ampere power sockets into safety banana female connections. To watch voltages of 3-phase networks with analyzers on long periods, to carry out reliable insulation tests on 3-phase networks.