New Balance Women's NBx Minimus Racerback Top 70% Polyester/25% Nylon/5% Spandex Imported Polygene technology uses recycled, all-natural silver salts to inhibit and suppress unsafe, odor-causing microbial growth Polygene technology uses recycled, all-natural silver salts to inhibit and suppress unsafe, odor-causing microbial growth Polygene technology uses recycled, all-natural silver salts to inhibit and suppress unsafe, odor-causing microbial growth