Hello Andy,
I saw the earlier references to "pipe threads".
And I'm gonna be picky here.
Pipe threads are normally tapered.
I had assumed that VW would address the NPT series of pipe threads
Yes, there are straight pipe threads, but they are less common.
I do a lot of designing of systems that use compression fittings for tubing (Plastic and metal) and I would like to be able to distinguish easily in my drawings between straight threads and tapered threads.