This is the Balance Tube Assembly for the 2WD fuel tank breather system. This aftermarket part is a very nice reproduction of the original VW part.
You can purchase the Tank Grommets separately if you need them, or better yet purchase the entire Fuel Tank Reseal Kit to get everything you need for the job while you're in there!
Fits: All 1980-91 2WD Vanagon. Not for Syncro