Ha measuring block Micrometer special measuring block 20 block group measuring block 38 caliper special 12 block 0 level 1 level 2 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level 3 level