Our Healthy Posture Corrector Instrument contain 100% polyester. It can help correct unhealthy sitting or standing posture, present a healthier posture, wear it at all times, remind you to sit or stand upright at all times, and promote a more active and healthy lifestyle. The way to use it is simple: adjust the strap and wear it before use. It can correct posture, relieve back pain caused by poor posture, and correct hunchback.