Just got these in the mail and they look great. I see a lot of reviews claiming knock-offs, and while some may be it's important to do a little research. I have done some quick web searches and came back with the following. First of all, NOT ALL RAYBAN'S ARE MADE IN ITALY. Direct yourself to the Luxottica website and read that they have factories in both Italy and China. That being said I have seen some customer photos of fakes from China that are EXTREMELY FAKE! Poorly painted and do not have the correct markings there are some really bad fakes. The Made in China stamp does not necessarily mean you have an authentic pair, but an authentic pair can have this stamping. Here are some other authentic characteristics I've found online.- The inside left arm will have something like: RB 5154 20XX 49 [] 21 140This is the model number, color, lens size, and frame size.- The right side very well may say "MADE IN CHINA"- The inside of the bridge will have the lens size 49 [] 21- The metal bits holding the nose pieces on are stamped "RB", if you look through the nose piece you can see this- And apparently the knock-offs feel cheap. I take this to mean bumpy or uneven paint, overly light weight, and nose pieces bending too easily.Now here is where I'm not able to gather information but still feel confident these are authentic.My Wayfarers have RB inscribed in the left lens (right lens if you are facing me) and the 5154's with clear lens' do not. It makes sense to only inscribe the sun glasses under the assumption these clear lenses will be replaced with prescription, however I haven't' been able to confirm or deny this.The printed Ray-Ban on the front right lens of my wayfarers (left if you are looking at me) is small and white. The 5154's have a larger logo on the opposite lens with the addition of the Federal Trademark. From what I can gather authentic RayBan 5154's DO have this registered trade mark and the logo is in the correct place. Just different from most of the sunglasses.The best thing you can do is take them into a store and compare to an authentic pair. I will have the opportunity to do this later in the week and can update my review with any new findings.