Under armour heatgear short sleeve t shirt junior boys the kids under armour heatgear short sleeve t shirt has been crafted with heat gear fabric and moisture transport system that wicks sweat away from the skin as well as drying fast this under armour shirt also benefits from 4 way stretch fabric that allows for full mobility along with flatlock seams that reduce skin irritation and chaffing completed with the under armour branding to the chest boys base layer shirt short sleeves