China Ceramic Thrust Bearings Washers:Zirconium Oxide Ceramic (ZrO2) Retainer:PTFE Balls:Zirconium Oxide Ceramic (ZrO2) (Typical Examples) Heat-resistant 180C --- Washers : ZrO2 / Retainer:PTFE / Balls:ZrO2 Heat-resistant 400C --- Washers : ZrO2 / No Retainer (Full complement of balls) / Balls:ZrO2 Heat-resistant 1100C --- Washers : Si3N4 / No Retainer (Full complement of balls) / Balls:Si3N4Ball Door to Door international express delivery