Tzelatis 618 thermal socks, knitted with 50% Merino / 50% synthetic fibers. The thermal socks feature a "towel" knit throughout the surface, resulting in maximum protection, comfort, and warmth for the feet during demanding activities. They include two elastic areas, at the ankle and sole, for maximum stability. The length of the leg reaches above the calf, exceeding the length of military boot shafts.