Bobbi Brown The Koko/S is a Full Rim frame for Women, which is made of Acetate Plastic.Acetate is the most common material used for frame manufacturing. It has endless possibilities for color, texture, and patterns. It can even be laminated to create great visual effects, and it can retain a higher luster. Acetate is lightweight, so it is often chosen for its versatility in coloring as well as for its comfort. Acetate is made out of cotton seed fibers and plasticizers. This model features a Rounded Edges shape, with a Single Bridge.These Sunglasses work well for people whose style is: Classic.Ideal for usage with: Fashion.These sunglasses can accommodate prescription lenses. Please call our Customer Service Department to order prescription lenses for this model.Bobbi Brown The Koko/S Sunglasses come with a cleaning cloth and protective carrying case.These sunglasses are available with a mirror coating option on certain colors. Mirror coatings are suitable for protection from intense light. A mirror coating reflects back light and reduces the amount of light passing through the lens. This makes it more comfortable for eyes in very sunny conditions.The sunglasses are available on certain colors with gradient tinted lenses - Gradient tints are tints that start off at a darker color at the top of a lens and then gradually lighten towards the bottom of the lenses. These tints are great for fashion and for reading outside on sunny days. Gradient coatings work by allowing an appropriate amount of light to filter through in certain areas and less in places where protection is most necessary.