This frame with prescription clip completes the Carrera C SPORT/01, C SPORT/02, C SPORT 015/S, C SPORT 016/S, CARRERA EYEDRA, and TRANSFORMA sunglasses. It attaches simply to the inside of the shield frame. They are a safe bet for those seeking perfect vision while enjoying outdoor activities. The structure is coated in rubber: like a caress on the solar lenses. The special case includes assembly instructions.