Under Armour Men's Base 4.0 Long Sleeve Base Layer Crew Shirt -Meet the all-new UA Base—delivering the same trusted warmth without the bulk—now softer and smoother than ever for unmatched comfort on every adventure. UA Base 4.0 Extreme Baselayer is our warmest yet, delivering extreme warmth in the extreme cold Material wicks sweat & dries really fast 4-way stretch material moves better in every direction Updated fabric with improved stretch is softer & smoother for maximum comfort and easier layering Fitted: Streamlined fit that's not too tight or too loose 93% Polyester/7% Elastane Style: 6005300