Warby Parker Downing Sunglasses Polarized Walnut Tortoise EUC This Downing frame has the same winning proportions, round lenses, and keyhole bridge as the original—we’ve just scaled it up to fit wider faces (or anyone who wants an oversized style). Made from hand-polished cellulose acetate Prescription lenses are made from polycarbonate, the most impact-resistant material for sunglasses; non-prescription lenses are made from CR-39 for maximum clarity and color