As to the problems caused by using direct-path filter in casting industry in and out of China,our company adopts special ingredient and technology and produces the filter from the aspects of improving the spalling resistance, thermal stability, void fraction and enlarging the surface area. The performance indexes of the products reach or surpass the level of that of overseas. The filter plate can filtrate and absorb the small impurity in molten metal in a maximum degree, so that on the one hand, the air bubbles are forbidden in; on the other hand, the molten metal are changed from turbulent flow to laminar flow and become homogenized. Furthermore, the filters are able to filtrate the impurities and the relevant chemical reaction will be finished by daubing on several kinds of catalyst, so the quality of the casting are improved. Many European and American companies have authorized this kind of product.