516-403-26 Mitutoyo Steel Square Gage Block Set, 81pc Grade AS-1Mitutoyo Steel Square Gage Block Set (81 blocks per set) BLOCKS INCLUDED IN SET 1 Block = 0. 050" 10 Blocks = . 1000" . 1009" in . 0001" increments 49 Blocks = . 101" . 149" in . 001" increments 17 Blocks = . 15" . 95" in . 05" increments 4 Blocks = 1" 4" in 1" increments Grade AS 1 Precision gage blocks are the primary standards vital to dimensional quality control in the manufacture of parts. Mitutoyo offers a complete selection of gage blocks