0.0001" Ultra Precision 1-2-3" Blocks 2pcs/Pair 1 Hole

[Hole Size]: 0.5". [Accuracy]: Size: +/- 0.0001"; Squareness: 0.0003"; Parallelism: +/- 0.0001"; Height Accuracy in Pair: +/-.0001". [Durable Material]: Made of hardened tool steel and all six sides are precision ground. [Application]: These steel blocks can be used for set-up, layout, and inspection jobs. Perfect for machinists, woodworkers, metalworkers, and more.