Long rubber end tips on the bows of the lightweight, Grilamid TR90 plastic frame reduce slippage during activity, and enhance comfort. Polycarbonate lenses are polarized for glare reduction and enhanced contrast (Matte Black and Matte Blue frames have gray lenses; Matte Brown frame has brown 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