display devices; electronic display instruments; electronic display units; LCD units; touch panels; water level indicators; water level gauges; water level indicators for vehicles; water meters; oil level sensors; liquid level sensors; level indicators; electrical switches; computer network switches; electric switches; interactive touchscreen terminals; touchscreens; touch screen monitors; touch sensitive display and control screens; LCD monitors; liquid crystal display [LCD] units; touchscreen monitors; LED displays; computer touchscreens; touch screens; level sensors; monitoring instruments; pressure sensors; pressure indicators; power switches; pressure switches; sensor switches; level converters; current switches; voltage monitoring units; multimeters for measuring electrical voltage; voltage meters; computer display monitors