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®Technology:PRIZM™ LENSES:- 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.PRIZM™ POLARIZED LENSES:- Prizm™ Polarized features the maximized contrast and enhanced visibility of Prizm™ with the glare filtering benefits of Oakley HDPolarized.PHOTOCHROMIC LENSES:- A premium option for select single-lens eyewear designs, it darkens the lens automatically to help you adapt to changing light and always perform at your best. Note that even when the lens color lightens, it still filters out 100% of all UV.POLARIZED® LENSES:- Improving safety, comfort and performance, Oakley HDPolarized lenses filter out 99% of reflected glare without the haze and optical distortion that can come with polarized lenses made with conventional manufacturing techniques.HIGH DEFINITION OPTICS® LENSES: All Oakley lenses offer HDO® Technology with the following benefits:- Clarity: Conventional lenses can magnify images. HDO® precision gives less distorted vision across the entire field of view.- Refraction: With regular lenses, objects aren’t really where you see them. HDO® offers a truer visual image so your brain won’t have to work overtime.- UV Protection: All Oakley lenses block 100% of UVA, UVB & UVC rays and harmful blue light up to 400 nm.