FYI: anytime you purchase aviation parts outside the "normal" vendor network your due diligence needs to up a few levels. But to generally state Ebay and Amazon has a good chance of counterfeit part is not correct either. Have been buying parts from Ebay since day one and have had zero issues and while haven't bought any from Amazon recently no issues either. Regardless, there are a number of "aviation" 3rd party sellers that sell "counterfeit" parts as well and get nailed on occasion. By chance did you fill out an FAA SUP form on those spark plugs?
A hangar neighbor just bought a new in the box set of Snap-on sockets off eBay that were counterfeits. ALL THE sockets were cosmetically perfect but 1000th under sized. No AN hardware would fit the designated socket. Ask yourself why a seller has 20-40-plus NIB socket sets for such a reasonable price. Also why so many seller with the same products? It's like 20 franchises decided to liquidate the same month to the secondary market. A legit Snap-on driver could put 30% off on his truck and the thing would be empty in a week.
Are you sure they weren't the FDX (Flank Drive Extra) sockets? When those came out a few years ago, they sounded interesting, so I bought a set off the truck to try out. And when I tried to use them, they would not fit on a single AN/MS piece of hardware. Promptly returned them to my dealer and stuck with my regular flank drives. I know another A&P who had the exact same experience with the FDX. So perhaps they weren't counterfeit, they were just FDX
Oh, that's really interesting. I tested the same hardware on FDX sockets off the truck last Monday and they fit. I wonder if Snappy missed the mark on dimensions on initial roll-out. The very same new AN hardware fit both the flank drive and FDX, which failed on the eBay set. If you every test fit on the truck again, really curious if your experience tracks.
I think I'll see my dealer tomorrow, will have to bring some hardware with me and try it out He doesn't sell much SAE though, so it's also possible any sets he has on the truck might have been from earlier production runs.
