Our Magneto Therapy Back Brace Posture Corrector contain 100% Polyester Fiber. It can effectively correct poor body posture, help improve body posture, and keep the spine upright. The way to use it is simple: put your shoulders on the shoulder strap, fasten the belt around your waist, and adjust the size to make sure the product fits your body. Soft and breathable material, comfortable to wear, suitable for long-term wear.