Aerials; Ammeters; Barometers; Burglar alarms; Couplings, electric; Ear plugs for divers; Electric meters; Electric relays; Electric sensors; Electrical signal attenuators; Erasing magnets; Galvanometers; Photographic exposure meters; Scales; Security and fire alarms; Speaking tubes; Speed indicators; Theft alarms; Time clocks; Tripods for cameras