14.0MM-1.25MM 6g Steel Go Special setting and calibration gage plug SiNoGole Ended assembly (With Handle included) used to set up or calibrate split thread ring gages to ASME B 1.2 tool steel cold stabilized Rc 60-62 marked with size and tolerance Certificate of Accuracy is included. Certificate of Accuracy is included.Click HERE to read about additional Long Form Cert.