The ASO Ankle Stabilizing Orthosis is one of the most popular ankle supports with coaches, trainers and physical therapists. The contoured tongue provides exceptional fit and is constructed of light-weight yet durable Cool Flex material. This material also lines the inside back of the boot, providing increased comfort to the achilles area. The polyester-cotton laces are strong and resist shrinking.20 or the 25 universities in the AP top 25 wear the ASO or EVO ankle brace. 55 of the 65 schools in mens NCAA tournament 2009 wore the ASO ankle orthosis. ASO is the choice of champions.