The POC Iris Comp Goggle are advanced ski goggles for people who demand high precision with no risk of optical distortion. This is vital for competitive skiers in particular.The single lens POC Iris Comp Googles comes in white with three single-lensessupplied as a standard clear, blue, and darkorange to give you the best possible reading ofthe ground under different light conditions on theslope. There is also a smaller size for smallerfaces. Identical to the standard Iris Comp. VLT (visible light transmission is a measurement that specifies the percentage of light coming through the lens and reaching your eyes. A totally clear lens for dark conditions typically have around 90 VLT and a very dark colored lens with mirror for sunny conditions may have down to 10 VLT. Most all-round lenses will be found between 30 to 60 .