1970 up valve cover breathers, 1 nipple, 2 nipples, 3 nipples.

Your dancing around my question, and not answering it?
Your so called "knowledge" in all the applications for valve cover breathers.
Where does it come from?
You going by some book that was written by some enthusiast that never was an auto mechanic in their lives.
Those authors, editors don't know what they're writing about in the first place, lots of times, anyway.

I have sold numerous 2 port, 3 port, breathers here on this forum, in the past, and this is the first time that you had to stick your nose into one of my ads, so what gives about that?
I'd like to know, what pissed you off.