90% Airlume combed and ring-spun cotton, 10% polyester(athletic heather) and 52% Airlume combed and ring-spun cotton, 48% polyester all other colors. The best of the best in one style — subtle and wildly soft 1x1 micro rib, timeless high-neck and racerback silhouette, and an ultra-wearable mid-length cut. The Micro Rib Racerback delicately frames the body with a comfortable, stretchy fit courtesy of the softest Airlume cotton in the game, creating a staple style in its best form.