which brake pipe fittings do I need?

[Adam32]

I have a brass brake pipe connector that looks like this:




What fittings do I need to buy for this?

Should I buy 1 or 2?

1) http://www.automec.co.uk/collections/best-sellers/...



2) http://www.automec.co.uk/collections/best-sellers/...



Note the difference at the ends of the fittings.

[Adam32]

fatjon said:

Either so long as it's long enough to bottom out before you run out of threads.

So why the difference in the two designs shown in the picture? Both are exactly the same length.