The Anon M4 is the perfect choice for the most in mountain visibility, a clean snow goggle with a classic cylindrical lens for a smooth, modern look bolstered by new Perceive technology for enhanced clarity in all conditions. Anon's Perceive tech works to heighten definition and contrast for the clearest possible visibility in all weather conditions, and features a water repellent coating to reduce smudging and prevent water pooling in your eyeline. This version of the M4 comes with 2 anti-fog lenses: Perceive Sunny Onyx for sunny conditions and Perceive Variable Violet for middling conditions. Changing lenses is made super quick and easy via Anon's MAGNA-TECH® system, using a series of magnets to securely fasten the lens in place. Magnets also feature on the base of the frame, called MFI® (Magnetic Face Mask Integration). MFI® ensures compatible face masks hug you goggles, meaning no more cold noses and a sharper look.