I know a while back we had a thread about unmarked AN fittings being shipped by Vans (I think) and Spruce. I also remember that the main concern was metallurgy and burrs. Well today I had an interesting conversation with a guy who makes "AN-type" fittings for hotrodders. He started out by explaining that the big difference between the real stuff and his stuff is the documentation. This I knew. He went on to tell me how the real stuff has rolled threads with radiused bottoms, whereas his stuff has cut threads with very sharp bottoms. I guess I expected this. Finally, he told me how he drills the inner bore of his stuff slightly oversize to flow better. The difference was slight, but you can definitely see it. Don't get me wrong, the guy's a good guy and produces very nice work, but I gotta figure that cut threads combined with reduced wall thickness makes for a significantly weaker part. Since this stuff only carries highly flammable gasoline to the single engine of the airplane that I ride in, it shouldn't be a big deal, right? ![Roll eyes :rolleyes: :rolleyes:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)