Transducers, namely, photoelectric transducers and Internet of Things transducers, that utilize ultrasonic oscillations to test for stress and fatigue in metal and metal structures; couplers being data processing equipment; optical communication instrument, namely, optical fiber connectors, optical cable connectors, optical modules, optical fiber amplifiers, optical switches, active optical devices in the nature of sensors, passive optical devices in the nature of sensors, wavelength division multiplexers, optical network control equipment in the nature of routers, wireless routers, electrical apparatus for controlling wireless signals and optical network monitoring equipment in the nature of computer network servers, computer network hubs; dynamometers; optical apparatus and instruments, namely, optical readers, condensers, fibres, scanners, lamps, sensors; amplifiers; switches, electric; integrated circuits; semiconductor apparatus; magnets and blank magnetic disks