The strap is simple to use, soft and durable, and it will keep your glasses and sunglasses look fashion. Comes with adjustable loops on the strap cord to ensure that the strap will not easily fall off and to make suitable adjustment for the convenience of your head in any sizes and shapes. Our sport safety eyeglasses holder straps are designed to keep your glasses more secure around your neck, and allowing your glasses to be hung on your chest or rest on top of your head comfortably. No more afraid to have your glasses or sunglasses attached when you are running, traveling, biking, hiking, climbing,skiing, or when you are at work with your head down. Perfect Christmas Gift.