9 wear-resistant machine parts of ceramic or ceramic-metal compound bodies, namely gliding controls; pipes made of ceramic; apparatuses and instruments for the high-voltage current technique, namely over-voltage arresters, distribution and connection systems comprising line holders, connecting terminals, junction boxes and sockets, safety fuses, switches, switch contacts; electric and electronic control devices for machines of all kinds; switch contacts, ferrite magnets with soft-magnetic and permanent magnetic characteristics in ceramic or plastic combinations, assemblies containing ferrite magnets, namely relays, loudspeakers, locks and fasteners; piezoelectric and ferroelectric ceramic parts