Threaded Ring Gauge Long Form Calibration Certificate No Material Tool Steel Dimension Type Inch Gauge Type Go (Plus) Pitch Diameter 0.2164 in Pitch Diameter - Go Member 0.2164 in Thread Class 2A Thread Length 11/32 in Thread Size 1/4 In.-20 Thread Type UNC Compatible Holder Size 2T Finish Uncoated Gauge Design Adjustable Hardness RC 60-62 Included Certification Certificate of Accuracy with NIST Traceability Standards ASME B1.2 Tolerance Class X