Fowler 52 439 032 0, Premium Brand 1 2 3 Block Set

High Precision: This 1-2-3 block set has a surface finish of 6-16μ", parallelism of 0.0002"/1", and hardness of 55-60 HRC with the dimensional accuracy of 0.0001"/1" Easy Clamping Holes: Block set with a total of 5 tapped and 18 untapped thru holes for easy clamping and set-up Durable Material: Made of hardened steel (56-60HRC). This 1-2-3 block set includes a shop-hardened case for storage and has a 1-year warranty offered by Fowler High Precision Inch-Metric Conversion: Quickly switch between inch or metric units with a single click; allows you to set zero for intermediate or differential measurements; hold feature freezes display for later viewing