4.5 oz./yd, pre-shrunk 100% ringspun USA cotton. Heather Grey is 90/10 ringspun cotton/polyester. Other Heathers are 50/50 ringspun cotton/polyester. Reactive-dyed for longer lasting color. Ribbed crewneck collar. Back neck tape. Shoulder-to-shoulder taping. Double-needle stitching on sleeves and bottom hem. Tear away label. USMCA certified.