The Gauge Blocks are length measuring standards. The accuracies conform to GB, ISO, DIN861, GGG-G-15C standards. They are used for length measurement.Gauge Block Set Table - ISO 3650Item No.   Pcs.per set    Class    Series of nominal size (mm)      Blocks in set    Weight (kg)902-01          88              1,2                0.050~4.000                         2-49          1.57 (1.220)     -02          81              1,2                0.1001~4.000                        4-49          1.521 (1.182)     -03          36              1,2                0.050~4.000                          1-9            0.7 (0.544)     -04          35              1,2                0.10005~4.000                      1-9            0.678 (0.527)     -05          20              1,2                0.050~0.0590                        2-9            0.057 (0.044)     -06          9                1,2                0.0625~2.000                        9               0.274 (0.213)Note: in the parenthesis is the weight of ceramic gauge blocks.