The ceramic seal faces/rings are classified into three grades:95% ceramic seal faces/rings,99% ceramic seal faces/rings,99.5% ceramic seal faces/rings according to the contents and of course there are some chemical and physical property differences among them which you find in the material property in our web. A ceramic seal face is charaterized with good resistance to corrosion and friction and can work properly in a lower temperature compared to silicon carbide seal face/ring,but in a higher temperature compared to a carbon seal face/ring.