Amplifiers; Anemometers; Camcorders; Earphones; Microscopes; Oscillographs; Scales; Batteries, electric; Educational apparatus, namely, manipulative blocks used as teaching aids for the visualization of math concepts; Instruments for measuring length; Loudspeakers with built in amplifiers; Magnifying glasses; Measuring glassware; Mobile telephones; Protective films adapted for smartphones; Tool measuring instruments; Video screens; Voltage stabilizing power supply; Audio amplifiers; Infrared ...