I have a male fitting. (it was screwed into one of the hoses of my ill fated plasma torch). Now that I removed it, I can use it to identify threads on the torch.
Thread OD = 14.23mm = .5605 inch
Exactly four steps of this thread take 0.2740 inch or 6.96mm. That means 4*1/0.2740 = 14.59 TPI.
I do not place great faith into my measurement of thread step, but I tried very hard.
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