The sleeker last and elegant features of the Ice Collection™ offer the same dry and warm protection as the original Rimfrost boots. Breathable and waterproof HYDRO-Tx membrane prevents water from entering into the foot-part up to the zipper. Duralon shaft with heat-insulating Thermolite® lining to keep legs and feet warm. Removable insole of cozy, warm pilelining Stirrup Control System incorporated in the outsole, and a steel shank for stability.