Calibrated steel balls are high-precision instruments used in metrology and applications requiring extremely accurate measurements. Made of ground and lapped chrome-plated steel, they guarantee high hardness, wear resistance and dimensional stability. They are manufactured to very tight tolerances on diameter and roundness, making them ideal as reference standards for precision measurement.

Often sold in pairs, they allow a direct comparison that improves measurement accuracy. Used to check measuring instruments and surfaces, they allow dimensions to be compared and the symmetry and roundness of mechanical components to be assessed.

In the measuring sector, they are used in the calibration of micrometers, slide gauges and co-ordinate measuring machines. Placed in holes or cavities, they precisely determine the internal diameter of a component and assess its geometry. Due to their precision, they are used to verify the reliability of measuring instruments and for roundness tests, which are essential in quality control in areas such as precision mechanics, automotive, aerospace and tool production.