Built with Under Armour's Lightweight ColdGear,the Under Armour UA Base 1.0 Leggings for Boys are ideal for training when the temperatures are under 55F and the exertion levels are high. Moisture wicking and quick to dry, the Base 1.0 Legging has flat lock seams for all-day chafe-free comfort and ArmourBlockTechnology, reducing odor and keeping you feeling New.