CW-X Men's Stabilyx Tights Our patented exo-web provides excellent targeted joint support to the hip, pelvis, knees and calf The exo-web provides targeted support to lower abdominal muscles, back and hamstrings and calf for extra stability and power Coolmax fabric helps keep the body dry by pulling moisture away from the skin The exo-web works to band together the muscles and ligaments of the knee joint. This helps to stabilize and support the joint Reflective "flash" for safe night time running