Features—No. 53-671 Series:
- Constructed of a special steel of high carbon & chrome content, hardened to 65RC, ensures hard wear resistance and stability.
- Manufactured under carefully controlled conditions to ensure maximum accuracy, parallelism and flatness.
- Calibrated to Fowler specifications which meet or exceed ASME B89.1.9-2002.
- Sets include certification traceable to the National Institute of Standards & Technology.
- Surface finish: .4 millionths (.01 microns).
Features—No. 53-670 Series:
- 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.