ANSI/ ASME B1.20.6 – 1984 which is Metric translation of ANSI B1.20.5-1978 & American Handbook H-28 Part II – 1957.
Taper Thread Plugs L1 & L3 in both Basic & Step Limit Design, Plain Taper Plugs to check crest of Threads,
Taper Thread Rings L1 & L2 in both Basic & Step Limit Design, Plain Taper Rings to check crest of external threads (6 step design), Master Check Plugs to check Thread Rings L1 & L2.
Pipe Sizes covered are from 1/16″ to 3″
For more Technical Details download Technical Information sheet from link given below.