Item NO.:JMX3~JMX16,JMX3T~JMX16TBall: Gcr15 Steel, heat treated, HRC56 min; Precision ground polished hard chromium plated Body: Steel alloy, heat treated, Zinc plated, chromate treated Race: Steel alloy, heat treated, Zinc plated, chromate treated Sliding contact surfaces: Steel/Steel or Steel/PTFE compositePhone: +86-592-580 8851 / +86-592-580 7618Email: sales@ldk-bearing.com ; benjamin@ldk-bearings.com