The U.S. military wanted a high performance gray lens for their aviators, so we made them one. When split-second decision making based on perfect color vision could be a matter of life and death, pilots of the U.S. military depend on the perfection of BPI® tinted lenses and tints. BPI® Aviator™ Gray-15 meets the specifications for the performance of their mission and the UV protection and health of their eyes. It has an almost flat transmission curve for minimal color aberration and a unique subtractive curve above 600nm to minimize red flair. Lenses can be tinted at all densities and the performance characteristics are the same at 15% transmission as they are at 90%. The U.S. military wanted a tint that would not shift color vision, and would enhance photopic and scotopic vision. BPI® Aviator™Gray-15 is a fast tinting dye that only takes about 10 minutes to reach 85% density. It is guaranteed to reduce tinting time for dark sunglass lenses, fade resistant and meets all U.S. and international standards for color recognition. BPI® Aviator™ Brown-15 allows pilots to have faster night vision adaptation and is useful for activities where critical visual discrimination is important. The U.S. military got all the performance they ordered.