Lightweight, durable, and flexible Grilamid TR90 plastic frame. Polycarbonate lenses are polarized for glare reduction and enhanced contrast. Blue Tortoise frame has blue polarized lenses; Tortoise frame has brown polarized lenses. UVA and UVB protection.California residents, read the Proposition 65 warning California Proposition 65 Warning California's Proposition 65 requires us to warn our customers if a product contains chemicals known to the State of California to cause cancer, birth defects or other reproductive harm if exposure to those chemicals is above set limits. For this product, we provide the following warning: WARNING: This product can expose you to chemicals including Bisphenol-A (BPA) which is known to the State of California to cause birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov