Front LineÖ MX is the latest addition to Oakley's High Impact line of goggles. With a Large to medium sized fit, Front LineÖ MX is optimized for a wide variety of faces and is engineered to fit perfectly with most helmets. Designed with Oakley's Ridg elock Technology, changing lenses is quick and easy while still allowing for a complete lens seal to prevent harsh conditions from penetrating into your goggle. Discreet frame notches at temples provide compatibility with most prescription eyewear. E ngineered to fit securely with most helmets without compromising fit. Discreet frame notches at temples provide compatibility with most prescription eyewear.