Threads as datums

In ASME Y14.5 2009 it's stated that it's okay to use threads as datums.

This is telling us to select the feature axis "B" which is a calculated result of the thread pitch.

If it's the intension use the major diameter as our datum simulator we need to communicate this next to the datum as such...

Now the reader knows for sure that it's okay to use the outer most surface of the threads as a datum regardless of feature size (RFS).