I was originally going to get Glock factory NS on my new Gen 4 Glock. However, there was some confusion and I got Trijicon instead. I paid something like $20 more for the Trijicons. Clearly the place I got it from was confused because when I called back, one person said that the Glock NS were plastic, another person said they were metal and Tenifer coated. I never actually saw the Glock NS. So, I called glock to ask them. Glock informed me that although the Glock factory NS are metal, they are not Tenifer coated. Perhaps they were at one point, I don't know. But, he assured me that they currently are not Tenifer coated. So, my guess would be that the finish of the Glock factory NS is on par with the finish on the Trijicons I have. If the Glock were actually Tenifer, I might have preferred them more since I would assume the finish would be tougher then than the Trijicons. But, since they're the same, I guess the $20 isn't much more for what might be slightly better sights. I just thought I'd pass this along since I still see people saying that the factory NS are Tenifer.