… devices, including photovoltaic cells whether or not assembled in modules or made up into panels; light-emitting diodes (LED), whether or not assembled with other light-emitting diodes (LED); mounted piezo-electric crystals. …
Explanatory notes
… devices, including photovoltaic cells whether or not assembled in modules or made up into panels; … for instance, of certain ores (e.g., crystal galena), tetravalent chemical elements (germanium, silicon, etc.) or … depends on the variation in resistivity between two of the terminals upon the application of an electric field to the …