Sauter AHB hardness test blocks are reference standards used for calibration and verification of hardness testers. These Sauter hardness test blocks provide known hardness values for checking instrument accuracy and ensuring traceable measurement results. They are used in hardness testing of metals to validate Leeb UCI or Shore devices depending on the block type. The blocks support routine calibration procedures in laboratories workshops and quality control departments. Using certified hardness test blocks ensures measurement reliability and compliance with testing standards. As calibration artefacts they are essential for maintaining hardness tester performance.