Under Armour Men's Base 4.0 BY9N4DHK_5FX5R

Looking for a baselayer that will keep you warm in the most extreme conditions? Look no further than the ColdGear Base 4.0 Mens Long Sleeve Crew. This baselayer is our warmest yet, thanks to UA Base 4.0 Extreme technology that locks in your body's heat to deliver extreme warmth. The soft, brushed grid interior traps air against your skin, closely managing your body's microclimate to keep you comfortable, while the material wicks sweat and dries quickly. The 4-way stretch construction ensures a full range of movement, so you can stay active even in the coldest weather.