0551 in to 0.0600 in, Dimension Type Inch, Gauge Type Go (Plus), Included Certification Certificate of Accuracy with NIST Traceability, Surface Finish 4 Microinch or Better, Tolerance 0.00004 in, Tolerance Class X, Hardness RC 60/65, Long Form Calibration Certificate No, Overall Length 2 in, Standards ISO 17025.