The Mitutoyo 516-960-26 gage block set includes 47 ASME grade AS-2 steel rectangular gage blocks with nominal size engraved in millimeters.
Blocks included in the set are (1) 1.005 mm, (9) 1.01 to 1.09 mm (steps of 0.01 mm), (9) 1.1 to 1.9 mm (steps of 0.1 mm), (24) 1 to 24 mm (steps of 1 mm), and (4) 25 to 100 mm (steps of 25 mm). Grade AS-2 blocks are generally used within workshops and can be slightly less accurate than AS-1 blocks.
Gage blocks (also called gauge blocks, Hoke blocks, Jo blocks, slip gages, and Johansson gages) are blocks used to calibrate measuring equipment and to standardize the measurement of length in manufacturing industries. They are commonly made of precision-ground steel, ceramic, or carbide material, and have a square or rectangular base. Each block has a unique identification number. Length is in inch or millimeter measurement. They can be sold individually, and are also sold in sets with blocks of varying lengths. Gage blocks can be wrung together to create a required length. Wringing is the process of lapping blocks together with a small amount of oil. They are standardized by grade, which refers to the tolerance or deviation of an individual block from its nominal length. Gage block grades are defined for flatness, length, parallelism and surface finish. Some grades of gage blocks meet standards such as ASME, Association for Iron and Steel (AIST), and International Organization for Standards (ISO). Application and required level of accuracy dictate which grade of gage block should be used. Some manufacturers provide an internally-generated certificate of inspection to verify that a gage block meets grade standards. Gage blocks can also go through a calibration certification process to verify measurement accuracy. Calibration is performed by an accredited facility. Gage blocks are commonly recalibrated after use to ensure dimensional accuracy. If a gage block does not meet calibration standards, it should no longer be used. Both a certificate of inspection and a calibration certificate specify the deviation from the nominal length.
Mitutoyo manufactures precision measuring tools, metrology equipment, and systems. The company was founded in Tokyo in 1934 and formed Mitutoyo America Corporation in 1963, which is headquartered in Aurora, IL.