Features: Light weight nylon eyeglass retainer strap ensures secure, slip ressitant wear during intense workouts, combining durability with light weight comfort for sports glasses, eyeglasses and eyewears accessories. Flexible length adjustment accommodates most head size, featuring water resistant properties for extended outdoor sports. Designed for men, women, active runners, cyclists, beachgoers, and individuals who prioritize eyeglasses security during high motion activity and social gatherings. Maintains eyeglasses positioning during running, gym fitness, mountain biking, swimming pool, themed event, or daily commutes with sweatproof construction. Compact rolling up designs enables effortlessly storage in pocket or backpacks while retaining shape integrity through repeated use. Specifications: Component: Nylon Color: Black, Redness and Black, Black and Gray Size: Approx. 30cm/11.81in Weight: Approx. 25g Package Includes: 5Pieces Glasses Strap Neck Cord note: 1.Please allow 0-1cm error due to manual measurement. Be sure you donot mind before bid. 2.Due to difference between different monitors, the picture may not reflect the actual color