1-2-3, 2-4-6, And Block Sets
Used in layout and setup work. Each set consists of 2 matched,
hardened and precision-ground blocks. The squareness on all
sides is within .0001” per inch. The blocks are supplied with a
plus allowance of .0001” to .0003” to allow nominal lapping. Five
3/8”-16 tapped holes are provided for clamping.