Ceramic bearings provide by sunyoung industry have the advantages of high intensity, abrasion-resistance, heat-resistance, insulation, low weight, magnetism-resistance, and corrosion-resistance, which the metal materials don't own. 1) specifications: ball bearings 2) bearing rings: zirconia or silicon nitride 3) balls: silicon nitride, zirconia, or alumina 4) cage: ptfe, pa, peek or stainless steel, etc.