It features many excellent properties of low iron content, high purity, high cold crushing strength and so on. Suitable for insulation castable or pre-fab; It can replece dense material if the area do not contact with slag or melting metal. Also it is suitable for insulation brick. Specifically it can be used for roof and door of aluminum furnace, roof of iron runner, roof of induction furnace, door of coke oven, roof for iron or steel ladle, lining of heat treating furnace or ceramic furnace and so on.