Threaded Plug Gauge, Dimension Type Metric, Gauge Type Go (Plus), Handle Design Member Only, Included Handle Not Applicable, Thread Class 6H, Thread Size M2.5 x 0.45, Thread Type Metric, Tolerance Class X, Gauge Finish Chrome Plated, Gauge Length – Go Member 6.40 mm, Gauge Material Tool Steel, Hardness RC 70-72, Included Certification Certificate of Accuracy with NIST Traceability, Long Form Calibration Certificate No, Pitch Diameter – Go Member 2.21 mm, Standards ASME B1.16M