Natuworld 1Dozen(12pcs) Colorful Elastic Adjustable Reading Glasses Eyewear Eyeglass Cord Neck Strap Rope Chains Holder for Kids Cords Material : nylon with rubber band inside Cord lenght: 45~50 cm Cords width: 2.5mm/0.098 inch Color: 12 pcs per dozen color maybe random Weight: 61g