electric components, namely, fuse-holders, fuse-links, lamp-fuse-holders, voltage selectors, and indicators, namely, light emitting diodes, incandescence and neon lamps with holders, and appliance couplers, namely, appliance inlets and mains outlets with and without mains filter, plugs and sockets for tubes and relays, and test jacks and test probes, and combined elements consisting of different electric components, namely, connectors, switches, fuse-holders, voltage selectors, mains filters, and test jacks and test probes, switches and push-button switches, and input systems and keyboards consisting of switches, membrane switches, electronic components, membrane keyboards, and housing for fuse-links in low voltage residential applications