Sound level meters, vibration sensors, vibration meters; electric apparatus and instruments being electric control devices for adjusting vehicle seats, electric control devices for vehicle seats, electric actuators for adjusting vehicle seats; apparatus for sound recording, transmission or reproduction of sound, images, or data in the field of aeronautics; active noise reduction apparatus comprising electrical filters, signal generators, loudspeakers, microphones, signal processors, and electric circuits, namely, update modification circuits, fast fourier transform circuits, arithmetic circuits and inverse fast fourier transform circuits; active noise reduction apparatus comprising an electrical connection housing, a power source, electromagnets, vibration sensors, accelerometers, proximity sensors and electric actuators, digital active noise reduction electric circuitry, and adaptive filters for selective audio signal suppression; frequency indicators, frequency stabilizers, apparatus for frequency modulation, namely, electronic frequency converters

Aeronautical vehicles; aeronautical vehicle seats and structural parts therefor; suspension systems for aeronautical vehicle seats; backrests, fitted seat covers, seat cushions, headrests and safety belts for aeronautical vehicle seats

Non-metallic structures for noise suppression insulation being acoustic insulation for aircraft and helicopters; insulation for aeronautic and aerospace vehicles with soundproofing properties; soundproofing materials, anti-vibration materials being padding materials of rubber or plastic, vibration dampers being padding materials of rubber or plastic, sound-absorbing plates and sound insulating panels being acoustical insulation barrier panels, sound-absorbing panels being insulation panels for aircraft and helicopters, sound-reduction coverings being insulation panels and padding material of rubber or plastic for aircrafts and helicopters, sound insulating foam for use in aircrafts and helicopters, soundproofing insulation being acoustical insulation barrier panels or padding materials of rubber or plastic; all the aforesaid goods for use in the aeronautical field