The Victory Color Block Power Back Tank Swimsuit from Nike is made from Nike NX fabric. Nike NX is made from a highly durable, nylon and chlorine resistant spandex blended to handle the rigors of training and competition. It is built for superior shape retention to provide the support you need for a confident fit, so no matter how hard you go, Nike NX is your strong suit. Moderate open back Thin straps for a comfortable fit Medium Neckline Ideal for practice and race day 81% nylon / 19% spandex