Uniqlo Combination Pufftech Jacket. Size: XXL Color: Popular Navy. New, unworn, with tags. "Pufftech" uses high-performance padding with the latest fiber technology, making it light and warm. The hollow fibers, about 1/5 the thickness of a human hair, trap warm air, providing warmth. *Assuming a hair thickness of 0.08mm, compared to polyester fibers. It maintains its bulk and insulation even in environments with over 90% humidity.