When I received these rings, I was very impressed by the quality and design. They installed easier that I expected and I was presently surprised to find that they are made in the USA. My Problems began when I had an issue with my scope and had to remove it. The thread-locker supplied on the screws had took hold and I was unable to break it free despite trying every trick in the book. I finally had to drill it out. now i have to find a replacement screw. It could have all been avoided if Nikon hadn't put thread-locker on the screws, which likely wasn't even necessary in the first place.