Leeb Hardness Test Blocks are used for calibration the hardness testers according to Leeb method. Leeb hardness testing complies to ASTM E18, DIN 50156 and ASTM A956. Leeb Hardness Test Block is produced of carbon or alloy steel, has one tested area (operating side) which has the required hardness. The tested area will have several indenter prints as factory final final calibration tests. Also, each calibration block has it’s identification number on its lateral surface.