Check out our Eyewear Mounted Rear View Mirror and you will quickly see the superior design and quality of Heads Up! versus other eyewear mounted cycling mirrors. Heads Up! requires little if any adjusting and it's made from a strong, very lightweight, safe-to-wear polycarbonate composite and Kraton. As you mount Heads Up! on a pair of sunglasses you will see how easy it is to install. If you need to adjust it, simply bend it slightly to maximize the field of vision from the oval mirror. No Vibration Mounts To Any Glasses Will Not Damage Glasses Removable/ Adjustable No Hassle Installation Weighs only 0.1 ounces (3.1 grams)