Ceramic bearings materials Inner and outer rings:silicon nitride ceramic (si3n4) and zirconium oxide ceramic (zro2) Retainers:ptfe (standard), peek, pi, pa, ceramic etc. Balls:silicon nitride ceramic (si3n4) and zirconium oxide ceramic (zro2) Typical examples Heat-resistant 180c --- inner & outer ring:zro2 / retainer:ptfe / balls:zro2 Heat-resistant 400c --- inner & outer ring:zro2 / no retainer (full complement of balls) / balls:zro2 Heat-resistant 1100c --- inner & outer ring:si3n4 / no retainer (full complement of balls) / balls:si3n4 Ball bearings, single and double angular contact ball bearings, self-aligning ball bearings, thrust ball bearings, unit bearings, etc.