... corundum alumina, 95%~99% Alumina, Zirconia Ceramics2)Variety: ceramic ring, ceramic cup, ceramic needle/ball/base etc erose part3) Fetures ... , thermostability and seismic-resistance, durable and wearable, good sealing propertyThere is no any wear or leakage after 500 thousands ... and good for health4)Application widely used for seal ring, water seal ring, water valve/hydrovalve ceramic sealing part