Precision steel ball components used as rolling elements inside bearings. These are core components of ball bearings that support rotational movement between inner and outer rings. Typically made from high carbon chromium bearing steel (SUJ2), these high-precision products have strictly controlled sphericity, surface roughness, and hardness. Used in rotating mechanisms of industrial machinery, machine tools, automotive parts, and home appliances, with diameters ranging from 1mm to 50mm. Classified into precision grades 0-10, allowing optimal precision selection based on application. Demand exists for individual purchases during bearing replacement and as components for custom bearing manufacturing for special applications.