Heh heh it's not even remotely breast shaped ??? - more like an upside-down bottle of Amstel beer
Mind you it is a long time since I've been in the Netherlands, perhaps the ladies there have evolved since then
On my tractor at least, this pot - some kind of water seperator - is mounted just behind the dipstick. Mine has a 90 degree knuckle on the bottom with a half-inch pipe thread end. I simply screwed an airline quick-connector to that.
If your tractor is missing the separator pot, try following the 'raw' output from the compressor and see where it goes. The outlet pipe comes out from the front of the compressor cylinder head. My neighbours tractor has lost the separator pot, and his airline is connected directly to this pipe.
Be aware that the separator pot doesn't appear to include a pressure regulator (unless mine is faulty?) and of course there is no reservoir unless you have the air brake stuff fitted, so care is needed when using the airline - pressure can build up to scary levels in seconds if you don't keep letting it out
The compressor on my tractor has been exceptionally useful. In fact I last used it only yesterday, when I got to the field and discovered that I had a soggy tyre on my forage harvester.
Best regards
J-P