Oh I think that I also bumped into some M6s that were not the thread pitch that I had assumed them to be - that is what happens when you only normally use "standard" or "prefered" thread pitches - ie if its M4, M5, M6, M8, M10, M12 then you "know" what the thread pitch is - ie what places like RS supply is okay - but not it seems with cars - well not with VAG anyway!