For colder conditions and higher activity levels, the Under Armour Boys's Basemap 2.5 Crew Long Sleeve Shirt is Built for extreme and midweight layering. Offering ArmourBlock technology for superior odor suppression as well as strategic ventilation to keep you nice, this performance base layer delivers maximum mobility and a Strengthive fit during cold weather workouts. Built with a moisture transfer system and abrasion free fit, the Under Armour Basemap 2.5 Crew Long Sleeve Shirt for men provides cold weather Safe guardion and feels great against your skin.