This heavyweight Carhartt force poly-wool quarter-zip base layer Top features temperature-regulating wool blend material to keep you warm, dry, and odor free on the coldest days. Smooth flat-lock seams and tag less label enhance comfort. Rugged flex fabric moves with you. Fast dry technology wicks away sweat. There's a convenient zip pocket on chest. The mock-neck collar with quarter length zipper unzips easily to release the heat when you're working hard. The concealed thumb loops keep your sleeves in place when you put on another layer.