The new standard of lower spine protection and support. Reinforced lower spine panel. Dual pull Velcro adjustment system. Channeled hex-foam for maximum ventilation and support. Ergonomically designed to provide maximum support and mobility. High density thermal plastic rubber panel for impact resistance. Adult Sizes. Small (Sm) 28-32" Large (Lg) 36-38" 2X-Large (2XL) 40-42". Medium (Md) 32-36" X-Large (XL) 38-40". Youth Size24-28"