I ordered the keg cap
I ordered the keg cap, since I have 2 of the growlers and thought it would be nice to have eventually ( eventually because COVID is keeping all my favorite breweries from filling any customer owned growlers). I also ordered a lid for the insulated pint cup I received free with my first growler. I'm not sure I'll use the cup for beer, but I definitely will for coffee - hence needing a lid. The shipping was delayed for whatever reason, and I actually managed to almost forget that I ordered the stuff in the first place, until I got the request to leave a review. I cannot speak to the function of the keg cap, as I have no beer other than my own to try it out with, but the person I dealt with via email (Josiah) was very apologetic and helpful. So 4 stars.