The Anon M4S Goggle Lens (Cylindrical) gives your Anon M4 goggles maximum adaptability — swap to the right lens for the right conditions in seconds using Magna-Tech® magnetic technology. Cylindrical lens construction delivers outstanding peripheral clarity and Perceive® optics, with Integral Clarity Technology anti-fog treatment for crystal-clear vision all day long. M4S Compatible: Designed to fit Anon M4S goggles, lens compression case included. Magna-Tech: Magna-Tech® quick lens-change technology uses a magnetic interface for a seamless and secure lens-to-frame seal that makes for easy lens changes and unsurpassed lens retention. Cylindrical Lens: Cylindrical Injected Lens enhances clarity and peripheral vision while maximizing vent volume. Anti-Fog: Integral Clarity Technology Anti-Fog exceeds basic anti-fog treatment standards, delivering crystal clear vision that lasts. Case Included: Lens compression case included. All Anon products are backed by a 1-year warranty from date of purchase.