The sleeker last and elegant features of the Ice Collection offer the same dry/warm protection as the original Rimfrost boots. Duralon shaft with heat-insulating Thermolite lining to keep legs and feet warm. YKK Vislon zipper has elastic inserts for an individual fit. Breathable waterproof HYDRO-Tx membrane prevents water from enter into the foot-part up to the zipper. Removable insole of cozy, warm pile-lining. Stirrup Control System incorporated in the outsole, and a steel shank for stability. Heel fitted with shock-absorbing IPS system. Fabric: Duralon/Hydrotech. Lining: Thermolite.