Camera lens, wired television monitor, electronic burglarproof video monitor, electronic video lens, starter for use with ac/dc motor, fire sensor, gas alarm, gas sensor, integrated circuit chip, shield, mask, integrated circuit, printed circuit board, printed circuit substrate, integrated circuit base, plug socket, plug contact, computer terminal, electric pole, capacitor, transformer, constant voltage regulator, commutator, circuit relay, electric circuit panel board, electrical connector, electrothermal tube, electrothermal chip, electric contact breaker, electric switch gear, electric power protector, electrostatic discharger, electrostatic generator, electronic device cooler fan, electric loop controller, power converter, magnetizer for magnetic tapes, magnetic eraser for magnetic tapes, magnetic excitor for magnetic tapes, motor controller, power stabilizer, electric power supply, uninterrupted power supply, battery charger, ozone generator for use with air cleaner, automatic door opener, automatic door shutter, electric lock, electronic lock, electronic burglarproof lock, magnetic card lock