Rockwell Hardness Test Block-NIST Traceable-HRCN 35
NIST Traceable Rockwell Test Block. The new NIST Traceable Test Blocks for the Rockwell "C" Scale will provide complete traceability to NIST. These test blocks are ground, lapped and polished to a mirror finish of one micron. A NIST Traceable Certificate is furnished with each block at no charge. HRCN 35.