Aero Shoe Cover: Recommended for those seeking speed. The ultimate aero shoe cover combines an innovative shoe cover with an aero sock that was developed through repeated wind tunnel testing. Designed with no zippers or Velcro to maximize aerobic effect, it is made from the finest Italian aero fabric and windproof materials. Anti-slip is placed on the inside of the opening to prevent slipping. Leg fabric: 80% polyester, 20% elastane. Foot fabric: 60% polyester, 40% polyurethane. Recommended for those who pursue speed. Comfortable to use even in hot weather. Color: Black and White; Size: S (approx. 9.1 - 9.8 inches (23 - 25 cm); M (approx. 9.8 - 10.4 inches (25 - 26.5 cm); L (approx. 10.4 - 11.0 inches (26.5