Craft Sportswear Men's Warm Zip Mockneck Long Sleeve Base Layer Shirt: cooling/sport/bike/ski/run/sun/protection/top 61% Polyamide/ 35% Polyester/ 4% Elastane Made in US New design focused on perfection of thermoregulation 3D Knitted fabric is sport specific for maximum comfort Lightweight hollow fibers provide ideal thermal regulation Bodymapped zones keep you warm and dry Very elastic for full freedom of movement Seamless torso Zip mockneck has centered zipper for ventilation