Mueller Aircast Sport Ankle Brace provides maximum support after a severe injury and allows an athlete to get back to participation. This brace is specifically designed for the left or right foot to help prevent sprains. Using its innovative aircell technology and semi-rigid shells it provides maximum support and comfort. Pre-inflated aircells cushion the interior of the brace and conform to the contour of the ankle Semi-rigid shells form the exterior of the brace, and are designed for both comfort and support One size fits all - Brace can be customized by adjusting straps, heel pad, and aircells. One-Size-Fits-Most (Fits shoe sizes from women's 6 to men's 18).