Differential-current switches; line circuit breakers; motor protection switches; mobile person protection switches; mains overload filters; installation switches and installation main sockets as well as combinations thereof as concealed and surface mounted types; dimmers also for low voltage; gong-ringing devices; clock transformers; infra-red movement detectors; plugs and in-series adapters; multiple main sockets with and without cable; extensions, including lengthening pieces, elongation pieces and extension lines, all in this class; travelling plugs; plug-adapters; electrical installation material in this class and wiring devices in this class