Computers; Optical sensors; Radios; Transmitters of electronic signals; Photoelectric sensors; Amplifiers; Optical fibers; Chargers for electric batteries; Electro-optical instruments for use in inspection and measurement of industrial components; Electron microscopes; Polarizing microscopes; Microscopes for scientific purposes; Spectrometers for laboratory use; Scientific apparatus, namely, spectrometers and parts and fittings therefor; Electronic and optical communications instruments and c...