4.5 oz., 100% combed ringspun cotton fine jersey; Heather: 90% combed ringspun cotton, 10% polyester; White is sewn with 100% cotton thread; Rib sleeve cuff, leg cuff and collar; Side seam construction; CPSIA compliant tracking label in side seam; EasyTear� label; Innovative snap tape closure now made with 97% post-consumer recycled polyester.by switching to recycled polyester snap tape, lat apparel will save over 672,000 plastic bottles from landfills each year