1.overproof 2.wearable 3.corrosion-resistant 4.magnetoelectricity insulated-resistant 5.lubricative with oil deep groove ball bearings 6204:Ceramic bearing had its specialities such as ovenproof, wearable, corrosion-resistant, magnetoelectricity insulated-resistant, lubricative without oil, high rotate speed and so on. It can be used in extreme badly environment and special situation, can widely ...