UA Women's Knockout Tank Insanely soft, breathable fabric. 4-way stretch construction moves better in every direction. Material wicks sweat and dries really fast. Anti-odor technology prevents growth of odor-causing microbes. Strategic mesh panels for added ventilation where you need it. Classic racerback construction. Dropped, shaped hem for enhanced coverage. Fuller cut for complete comfort. 90% Polyester/10% Elastane.