The Heat Holders Oran Solid Knit RollUp Hat is made with high-performance thermal yarn for extra warmth and softness. The hat is also made with the luxurious HeatWeaver plush insulation lining, specially built to maximize the amount of warm air held close to your body, keeping your head warmer for longer even in the coldest conditions. The Oran Solid Knit RollUp Hat also uses fine rib construction and is sewn to better fit contours of the head further maximizing insulation and creating a more flattering style.