The Men’s UA Base™ 4.0 Crew was built to battle nature’s coldest and most brutal conditions. Its patented mega-grid fleece fabric traps heat to keep you ridiculously warm without feeling weighed down. It wicks away excess moisture in its unique grid channels—keeping you dry and comfortable no matter how hard you work. You can also move with unrestricted ease thanks to UA's super-stretchy fabrication. Facing insane temperatures? Get the performance crew that makes more sense—and delivers more warmth—than anything else out there.