Core's universal rib belt is constructed of a two-tiered, 6" elastic body for comfort and stability. Women's belt contours to 4" around bustline for a better fit. This belt can be worn against the skin or over clothing. Features a CoreEdge finish for comfort. For best fit measure at the widest part of the chest. SM/MD fits 24" to 36"; LG/XL fits 36" to 48".