Threaded Ring Gauge, Long Form Calibration Certificate No, Material Tool Steel, Dimension Type Inch, Gauge Type Go/No-Go (Plus/Minus), Pitch Diameter 0.1918 (Go), 0.1886 (No-Go), Pitch Diameter - Go Member 0.1918 in, Pitch Diameter - No-Go Member 0.1886 in, Thread Class 2A, Thread Length 3/16 in, Thread Size #12-28, Thread Type UNF, Compatible Holder Size 1T, Finish Uncoated, Gauge Design Adjustable, Hardness RC 60-62, Included Certification Certificate of Accuracy with NIST Traceability