Acetate Frame. Acetate is a plant-based plastic known for being lightweight, yet durable. Plastic frame - Crystal lens - Non-polarized - 100% UV400 protection coating - Lens width: 54 millimeters - Lens height: 40 millimeters - Bridge: 18 millimeters - Arm: 140 millimeters - 2" high - Slight adjustments to the shape and curvature of the sunglasses arms may be needed to get a custom fit. Adjustments should be made by a professional. Every model in the Ray-Ban collection is the product of meticulous, original styling that translates the best of the latest fashion trends into an ever-contemporary look for millions of Ray-Ban wearers around the world. Ray-Ban sizes refer to the width of one lens in millimeters. Protective case included, cases come in a variety of colors. Lenses are prescription-ready (Rx-able). Ray-Ban products include an etched "RB" on the left lens. The RB is not a scratch or defect. The shape and curvature of these sunglasses may need adjustments. Adjustments should only be made by a professional.