Prime-Series Thermal Balaclava Ergonomically engineered to provide the perfect fit across a wide array of faces. Fabric Content: 91% Polyester, 9% Spandex Knit. Fabric outer surface is engineered to disperse moisture for fast evaporation. Hydrophilic next-to-skin surface absorbs sweat and transfers it to the outside of your garment. Lightweight fabric keeps you extremely warm while preventing excess weight and bulkiness on your face. Polartec® Power Grid™ generates targeted touch points to manage moisture while grid design creates improved breathability.