... .Ring and balls made by full ceramic bearing material:Si3N4 2.OEM chinese bearing is OK,as per client' ... performance than ZrO2, the rings and balls made by full ceramic material:Si3N4, as a standard constructure,the cage made by PTFE ... -25,PEEK,PI, Phonemic Textiles Tube ,etc. Compares than the material of ZrO2 ,The SiN4 could endure heavier load and could be ...