The Oakley SI Speed Jacket features a stress-resistant O-Matter frame with a Three-Point Fit, which delivers exceptional comfort and performance. With this signature fit, the lenses are held in exact optical alignment, and the frame only makes contact at the nose and sides of the head, ensuring the these shades don't pinch or squeeze. Even as you work up a sweat, the Speed Jacket will stay comfortably in place thanks to the non-slip Unobtanium nosepiece. The Oakley Switchlock trigger assisted lens change technology lets you rapidly switch out the lenses, making it easy to adapt these sunglasses to suit your environment. The impact-resistant Plutonite lenses are made with a durable polycarbonate that filters out all UVA, UVB and harmful blue light up to 400 nanometers.