Acoustic amplifiers for mobile devices; Apparatus for recording, transmission or reproduction of sound; Batteries and battery chargers; Battery chargers for tablet computers; Earphones and headphones; Hygienic covers adapted for virtual reality headsets; Hygienic pads adapted for virtual reality head-mounted displays; Hygienic pads adapted for virtual reality headsets; Lenses for cellular phone cameras; Lenses for smartphone cameras; Signal processors for audio speakers; Sonar equipment and p...