- Each block is serialized, with a certificate detailing the environmental conditions used to test the block
- Actual readings are given, with the averages of these readings: min. reading, max reading and a repeatability figure
- The blocks are calibrated according to ASTM E=18 standards, ANSI (NCSL) Z540=1, (ISO) 10012=1, ISO/IEC 17025 and Mil=std 45662A
- Hardness test blocks are designed to be used on one side only
- Indents should be more than .010" from the centers of two indents or no closer to the block's edge than .040"