5/8 24 UNEF 2B Go & NoGo Thread Plug with Taperlock Style W/ Handle tool Steel Rc 60-62 cold stabilized work plug handles can be marked with 15 characters at no additional cost Inch handles will be light blue metric yellow Certificate of Accuracy is included NOTE: selection of a 2B or 3B is based on your requirements. A 2B class plug will have a larger pitch diameter for the NoGoThread member only. The Go member is the same regardless of the class chosen. Certificate of Accuracy is included.Click HERE to read about additional Long Form Cert.