the largest field of vision and sharpest optics. with the introduction of birds eye vision- â„¢ technology, the 4d magâ„¢ sets new standards and lets you see more than ever before. this state-of-the-art innovation expands the entire field of vision by 25 percent compared to the i/o magâ„¢. in addition, thanks to the double locking mechanisms integrated in the side arms of the frame, changing lenses is even simpler and faster. thanks to chromapopâ„¢, the 4d magâ„¢ takes you into a bigger, brighter and sharper world.chromapopâ„¢ sun red mirror lensthe more you see, the more you experience. smith's superior chromopopâ„¢ technology enhances the clarity of natural colours so you can see more detail without straining your eyes.transmittance of visible light: 16 %chromapopâ„¢ storm yellow flash lensmade to bring out the best in an environment when the storm is blowing in and the light is going out. optimises your contrast even on the worst days so you can stay out longer.transmittance of visible light: 65 %