Fowler Steel Rectangular Gage Block Set 36 piece set - Grade 0 Each block is rectangular steel and hardened to 65RC, stress relieved, lapped to accurate size, parallelism and flatness, then carefully inspected and marked for size; designed to meet close tolerances Each set includes standard sizes found in more expensive sets. Each block individually serialized; conforms to rigid standards of the National Institute of Standards & Technology Price includes fitted wood case Included in this set... 1 Block .05" 9 Blocks .1001" thru .1009" in 0.0001" steps 9 Blocks .101" thru .109" in 0.001" steps 9 Blocks .110" thru .190" in 0.01" steps 5 Blocks .100" thru .500" in 0.1" steps 1 Block: 1" 1 Block: 2" 1 Block: 4"