Never lose your eyeglasses again. Glasses strap will grip firmly the ends of your sunglasses, and keep them stay in place. It's inexpensive insurance for your expensive sunglasses. You could adjust it's length freely. Using them to keep your glasses more firmly in place when you doing exercise, also loosen the retainer to hang your glass comfortably on your chest. No need to find a place to put your glass. The premium Neoprene material is comfy, lightweight and elastic. It is comfortable, soft. Does not to stimulate skin.