These are authorized resellers of ASTM standards. They often offer bundle deals if you need multiple standards (e.g., ASTM E8 + ASTM E83).
is the definitive international standard titled "Standard Practice for Verification and Classification of Extensometer Systems." Published by ASTM International (formerly the American Society for Testing and Materials), it is the most widely recognized document governing how extensometers—the devices that measure strain in tensile and compression tests—are verified and graded for accuracy. astm e83 pdf
: Step-by-step methods for calibrating extensometers against known reference displacements, such as calibrated micrometers or gauge block systems. These are authorized resellers of ASTM standards