Felix Grays amber lenses are made out of High Impact 1.56 lenses, which is a super lightweight and impact resistant material. It has a very high Abbe value and is optically superior to polycarbonate lenses. While the lens tint is more yellow than the Felix Gray proprietary clear lens, our amber lens specifically filters more of the range of Blue Light that is most disruptive to our natural sleep cycle in the 440 nm - 500 nm range. The soothing amber color slightly dims the light intensity, making them ideal for unwinding before bedtime.