I bought this from MJM autohaus, turns out I don't need it. Never installed, obviously. I paid $15 for it, I'll pass it on for the same price. No sense in keeping one laying around if I don't need it.

OEM part # 050121113C. Behr is the manufacturer.

According to MJM, it fits:
1998-2005 Passat 1.8T
2000-2006 Audi TT 1.8T
1998-2005 Beetle 1.8T/2.0L
1999.5-2005 Golf-Jetta 1.8T/2.0L
1997-2001 Audi A4 1.8T (AEB/ATW/AWM)