0 0 6909 Ceramic wares for laboratory, chemical or other technical uses; ceramic troughs, tubs and similar receptacles used in agriculture; ceramic pots, jars and similar articles used for the conveyance or packing of goods (excl. millstones, polishing stones, grindstones and the like of heading 6804; refractory ceramic goods; household articles; containers for shops; electrical devices, insulators and other insulating fittings)