Since 1998, as an ISO 9001: 2000 Certified company, we are a leading manufacturer of high quality ceramic seal ring in China Our products have excellent performance of Good sealing, Excellent Resistant-Corrosion, High-Temperature Resistance , High Mechanical Strength, High hardness , Stable chemical property ,Wear Resistant, High Thermal Conductivity, Good Self-Lubrication, High purity alpha alumina and low silica content, Small Tolerance Range , Long Time Warranty, Stably and Professional Quality Control. Surface Treatment: Polished, Alumina Purity: 95% to 99.5%, Color: White, Creamy. Sizes: Various sizes available. Welcome to contact Steven: skype:vital-sales5.