Lululemon Mens Metal Vent Tech Long Sleeve Shirt 100% Polyester Seamless construction, anti-stink technology, and strategic venting make this shirt training-session ready. Sweat wicking fabric is 4 way stretch. Silverescent technology, powered by X-STATIC, inhibits the growth of odor-causing bacteria on the shirt. Mesh venting encourages airflow and keeps you cool. Seamless construction reduces bulk to help prevent chafing 50% polyester, 47% nylon, 3% X-STATIC nylon.