Kilpi NATHAN-JB long-sleeved thermal T-shirt for boys is made of quick-drying OPTI-DRY material, which is pleasant to the touch, extremely elastic, wicks moisture away from the skin well and thus maintains thermal comfort. The shirt has a round neckline. Seamless knit with flat seams and a close-fitting cut that follows the curves of the body and maximizes comfort when moving and wearing. We offer NATHAN-JB in two colors and several sizes. We recommend that you also get the Kilpi NIEL-JB underpants as a great set not only for skiing, hiking, but also for other outdoor activities.Material composition: 53% polyamide, 41% polyester, 6% elastane