What are G-15 XLT lenses?

G-15 XLT lenses are used on Ray-Ban sunglasses and are rated to block 85 percent of light going through them. These lenses are green in color and block 100 percent of ultraviolet light from the sun.

An alternative to the G-15 XLT lenses are the B-15 XLT lenses that provide the same UV and light protection levels, but they are colored to eliminate more blue light to create better contrast. The two types of lenses were originally created during the 1930s as part of a U.S. Air Force commission for Ray-Ban to create lenses that would block nausea-inducing glare during flight.