Sports Sunglasses are made of TR90, and it is safety, lightweight, wear-resistance and toughness. You can hardly feel them on your face,yet they are unbreakable, can effectively protecting your safety. It has good chemical resistance and is not easily deformed in high temperature environment real tr90 optical frame. TR90 optical frame can use for 3 years at least, and is difficult to break up. It fits right on the face which can adjust the width,preventing it clip your face and fall down. Its nose pad scan adjust to fully fit the bridge of your nose ,it has increased the applied force area,lightening your burden,reducing discomfort caused by prolonged wear and can not leave imprint .