Oakley engineering takes performance to the next level and brings style along for the ride. Flak 2.0 offers a standard size frame with enhanced lens coverage, and every millimeter of the lens is optimized with High Definition Optics in a ruggedly durable yet lightweight design. Designed to push your limits with patented XYZ Optics for razor sharp clarity and secure grip of Unobtanium. Prizm is a revolution in lens optics built on decades of color science research. Prizm lenses provide unprecedented control of light transmission resulting in colors precisely tuned to maximize contrast and enhance visibility. To help maintain the High Definition Optics (HDO) of Oakley lenses, your new eyewear comes with a specially-woven electrostatic Microclear bag for cleaning and storage. Using it will preserve the superior optical quality of Oakley's pure Plutonite lenses. Hand wash and air-dry the Microclear bag regularly. Colour: Matte Black. Lens colour: Prizm Dark Golf.