The SmartWool Mid 250 Pattern Zip Top is a versatile piece that will take your kid from shoulder-season trail running to skiing and back again. Whichever way he makes his way around the mountains, this baselayer's merino wool regulates his temperature and manages moisture from sweat to keep him comfortable. The flatlock seams are designed to protect his skin from chafing, and the interlock knit is luxuriously soft and breathable to keep him comfortable for long days on the trail or slopes.