Size: M (133mm) Oakley® Sylas is a classic frame with reliable features. Feel secure in this new style that goes above and beyond the standard with upgraded features for all-day wear, including a hat compatible design, lightweight frame and Prizm™ Lens Technology. • HAT COMPATIBLE: hat compatible frame and temple design with an increased extended periphery • SEE MORE DETAILS: Available with Prizm™ lenses that are designed to enhance color, contrast and detail to make the most of any activity • FIT: Three-point Fit is designed for comfort and to hold your eyewear in precise optical alignment • LIGHTWEIGHT: Lightweight O Matter™ frame material provides durability and all-day comfort • PRESCRIPTION: Available with Oakley Authentic Prescription lenses for athletes of all levels with RX needs