The warmest Under Armour base layer on the market. The Under Armour Base 4.0 Long-Sleeve Crew's odor-reducing ArmourBlock® technology keeps it fresh for multiday wear. Flatlock stitching and ergonomic seams prevent bunching and offer an unrestrictive fit for total comfort. Crew neck for nonbulky layering and raglan sleeves for freedom of movement. Made of heavyweight 7.25-oz. 96/4 polyester/elastane for premium softness and stretch. Imported. Sizes: S-3XL. Color: Black.