... ,High speed. 3,End cover:ZZ. 4,Noise level:Z1,Z2. 5,C2,C0,C3. high Performance ceramic ball bearing-china bearingWe ... have 2 types of ceramic bearing, hybrid ceramic bearing and full ceramic bearing, the hybrid ceramic bearing has steel inner and outer ... and the balls are made of ceramic. There are many kinds of ceramic materials, the most common ceramic materials are Si3N4 that stands ...