Threaded Ring Gauge, Long Form Calibration Certificate No, Material Tool Steel, Dimension Type Metric, Gauge Type Go/No-Go (Plus/Minus), Pitch Diameter 2.188 mm (Go), 2.117 mm (No-Go), Pitch Diameter - Go Member 2.188 mm, Pitch Diameter - No-Go Member 2.117 mm, Thread Class 6G, Thread Length 4 mm, Thread Size M2.5 x 0.45, Thread Type Metric, Compatible Holder Size 1T, Finish Uncoated, Gauge Design Adjustable, Hardness RC 60-62