Comfort Fit Therma Tek (formerly Winter Men's Thermal 100% Cotton Top & Bottom 2 Pcs Set Black Imported Men's thermal 2pcs set, including top and bottom. 100% cotton. Soft cotton-rich knit feels soothing against skin. Breathable waffle texture. Stretchy ribbed cuffs fit comfortably. Stay warm all winter. Sturdy seams help ensure lasting wear. Classic crewneck. Machine wash.