6903 Retorts, Crucibles, Mufflers, Nozzles, Plugs, Supports, Cupels, Tubes, Pipes, Sheaths, Rods and Other Refractory Ceramic Goods (Excl. Those of Siliceous Fossil Meals or of Similar Siliceous Earths, and Refractory Bricks, Blocks, Tiles and Similar RefractOry Ceramic Constructional Goods)
6903 Retorts, Crucibles, Mufflers, Nozzles, Plugs, Supports, Cupels, Tubes, Pipes, Sheaths, Rods and Other Refractory Ceramic Goods (Excl. Those of Siliceous Fossil Meals or of Similar Siliceous Earths, and Refractory Bricks, Blocks, Tiles and Similar RefractOry Ceramic Constructional Goods)