SPI - Standard Test Blocks


  • Standard test blocks provide and easy means of checking your tester's accuracy.
  • Periodic testing on a regular basis is recommended.
  • Comparing a test reading of the block with the hardness number on the test block will indicate whether or not the instrument needs attention.
  • A surface rating of less than 5 micro‐inches (CLA), and both test and supporting surfaces flat and parallel prior to being calibrated.
  • Order the hardness range and scale which is approximately the same as the work you will be testing.
  • Approximate sizes: 1 1/2"L x 2 1/2"W x 1/2"H.
SPI Test Block - Hardness: 20-30 HRC Scale - Type: C