5.0 oz., 100% combed ringspun cotton 1x1 baby rib ; Heather is 88/12 combed ringspun cotton/polyester; White is sewn with 100% cotton thread; 5 oz. 100% combed ringspun cotton 1x1 baby rib; Heather is 88/12 combed ringspun cotton/polyester 1x1 baby rib; Ribbed collar and cuffs; Self-fabric back neck tape; Double needle bottom hem; Flatlock stitched seams; Side seam construction; EasyTear™ label; CPSIA compliant tracking label in side seam; Wear Snug Fitting. Not flame resistant. CPSC compliant y