Cocoon Eyewear Polarized Sunglasses completely isolate your eyes from the elements. They feature a unique design that provides 100% UV A, B, and C protection, and can be worn over prescription eyewear or as conventional sunglasses. After wearing Cocoons for a short period of time, your eyes will begin to relax. The polarized UV400 front lenses treat incoming light, reducing distracting glare and allowing you to focus on the task at hand. The patented frames protect your eyes from all angles, blocking sunlight, UV, glare, wind, rain and airborne debris. Grey lenses offer a neutral color definition. Amber lenses provide increased depth perception. Cocoons include a neoprene carry case, and a large lens cloth. Covered by a limited lifetime warranty from the manufacturer. To determine size, measure your prescription glasses from temple to temple and the height of the lenses. Select the frame size that is at least as large as these measurements. Sizes: Frames Fit over Glasses M5 14w x 1 12 h, L5 38w x 1 78 h, W5 58 w x 1 38 h. Wear over prescription eyewear or as conventional sunglasses. 100% UB A, B and C protection. Polarized UV400 front lenses. Neoprene carry case included. Large lens cloth included.