ColdPruf Men's Extreme Performance Dual Layer Long Sleeve Crew Neck Base Layer Top 96% CPT Performance Polyester / 4% Spandex Imported Two-layer engineering traps body heat between layers, resulting in chill-blocking warmth Drop tail maintains coverage in various activities Tagless labeling and flat seems provide a smooth fit and extra comfort Moisture management wicks perspiration and dries quickly Featuring ColdPruf Technical Fiber formulated with Silvadur Intelligent Freshness to minimize odor and odor causing bacteria on fabric Best used as a base layer or mid layer in very cold to extreme cold weathers or as outerwear in cool situations