Class X Go Pin Gauge, Material Steel, Finish Uncoated, Diameter 0.9948 in, Diameter Increment 0.0001 in, Diameter Range 0.7601 in to 1.0000 in, Diameter Sub-Range 0.9901 in to 0.9950 in, Dimension Type Inch, Gauge Type Go (Plus), Included Certification Certificate of Accuracy with NIST Traceability, Surface Finish 4 Microinch or Better, Tolerance 0.00006 in, Tolerance Class X, Hardness RC 60/65, Long Form Calibration Certificate No, Overall Length 2 in, Standards ISO 17025