This posture support is made from the finest quality beige elastic materials. It serves as a gentle reminder to hold the shoulders in a natural, correct posture, and to help prevent strain and fatigue. It is an excellent choice for the workplace to help prevent slumping shoulders and poor posture. The support is specifically designed for wear while performing highly repetitive tasks like data entry. How to Measure: Measure around the waist. Size Fits Extra Small waist 25.0-28.5 in. Small waist 28.5-31.5 in. Medium waist 31.5-35.5 in. Large waist 35.5-39.5 in. Extra Large waist 39.5-43.5 in.