Our warmest beanie to date. You won't want to leave home without the Bruggen hunting beanie made with Heat Boost graphene technology. Heat Boost is a line of graphene-enhanced material and a pioneer in the next generation of advanced fabrics with new functionalities. Knitting graphene yarn into our sherpa fabric supercharges it with graphene's thermal conductive properties, making a warm material even warmer - 30% warmer. This performance fleece beanie is fully lined with Heat Boost graphene short pile sherpa for outstanding warmth that you will quickly feel. The sides are curved to ensure your ears are covered. A DWR treatment on the exterior makes light moisture bead up and roll off the fabric. Pull on for all day lasting warmth.1 Year Limited warranty