Posture Corrector Adjustable Shoulder Back Straightener Breathable Back Support Brace BeltM Condition: Item Type: Posture CorrectorProduct Material: Fiber Elastic + Nylon + Polyester FiberSize Suitable Waist Suitable Height Suitable Weight Size Suitable Waist Suitable Height Suitable Weight XS  Under 50cm / 19.7in 100-130cm / 39.4-51.2in 15 ~ 25kg / 33.1 ~ 55.1lb S  33-66cm / 13-26in 125-155cm / 49.2-61in 25 ~ 45kg / 55.1 ~ 99.2lb M 66-80cm / 26-31.5in 150-170cm / 59.1-66.9in 45 ~ 65kg / 99.2 ~ 143.3lb L 80-93cm / 31.5-36.6in 160-180cm / 63-70.9in 60 ~ 75kg / 132.3 ~ 165.3lb XL  96-106cm / 37.8-41.7in 165-185cm / 65-72.8in Above 80kg / 176.4lb Scope of Application: 1. Adolescents have poor sitting and walking posture to prevent the habit of bending over and lowering their heads, hunched back and close eyes habits 2. Relieve back pain caused by standing for a long time, sitting at desk for a long time, maintaining the same posture for too long, etc. Instructions: Step 1: Stretch out your arms and put on the adjustment shoulder strap to the right position. Step 2: Pull down and level, adjust the position of the abdomen, and glue the rough surface of the abdomen. Step 3: Pull the end of the double Y cross-leader to the abdomen, adjust the tension properly and glue it. Step 4: After sticking the two adjusting straps, raise your head and straighten your back, slim! When using this product, try to straighten your waist and back, wear this product flat on your body, compact the hook and wool surfaces of the adhesive buckle, and pull the end of the double Y cross strap to the shoulder to adjust it to the maximum Good position, stick the protective buckle well to achieve the best pulling effect.