Soft, waffle knit thermal cotton-rich fabric.nTag-free for itch-free comfort.nSturdy seam construction for added strength and durability with smooth, flat no rub seams to prevent chafing.nPreshrunk for lasting fit.nSize up for a roomier fit.nKeeps boys comfy no matter what the activity. How? X-TempTM technology adapts to temperature, environment and activity to keep them cool and dry for all day comfort, Soft, waffle knit thermal cotton-rich fabric, Tag-free for itch-free comfort, Sturdy seam construction for added strength and durability with smooth, flat no rub seams to prevent chafing, Preshrunk for lasting fit, Size up for a roomier fit.