Hump Correction, Back Correction Strap, Corrector, Clavicle Strap, Ssitting Posture, Back Support, And Correction Strap Features: Supports Proper Posture and Relieves Back Pain. Strong breathable fabric makes it more comfortable to wear without stuffiness feeling. Can be directly worn under clothing. Adjustoble straps for comfort, help pull the shoulders back to stand tall & sit up straight. Supporting design helps correct poor posture, pulls shoulder back to correct posture. Product Description: XS: Fits waist size: 25.5-31.4; S: Fits waist size: 29.5-35.4; M: Fits waist size: 33.4-39.3; L: Fits waist size: 37.4-43.3; XL: Fits waist size: 41.3-49.2; Material: cloth + sponge + sandwich mesh Package Included: 1 X Back Brace