Disposable thermocouple for measuring of melt and different types of ceramic filters ( different diameters ) for uniforming of melt flow are classified in this group . ceramic Foam Filter is another product is included in this group and its types are SIC , AL2O3 . AND ZrO2 , different sizes and meshes : 30 , 20, 10 ppi for separation of melted impurities while iron , Aluminium and steel casting .