Dedicated thermal insulation: Insulation being especially important in women's boots, all our liners have specific thermal insulation in the form of Thinsulate, wool or polar fleece. The liners have > FULL THERMAL INSULATION with the material all around the foot. > FOREFOOT THERMAL INSULATION with the material around the forefoot in the toe box. WOOL - VITA / KELIA Familiar for centuries, natural wool is an excellent thermal insulator. It provides warmth and comfort in these models.