... :ring gauges 2.Material:GCr15 3.Type:Various types (Metric,UNC,UNF,BSW) 4.Precision:5H,6G,7H Metric ring ... gaugesFeatures: 1.Gauges:ring gauges2.Material:GCr153.Type:Various types (Metric, ... UNC,UNF,BSW)4.Precision:5H,6G,7H 5.Measuring hole ... ,please feel free to contact with us. Metric ring gauges