All the elements are in place to keep your feet warm, dry and comfortable. The Cold Weather Collection contains Vibram and eVent components. Uppers: All boots are made with waterproof full grain leather or waterproof nylon uppers. Insoles: Removable and replaceable sheepskin sock liner that naturally wicks away moisture and helps keep your feet dry. Breathable eVent Membrane. Outsole: Exclusive Vibram outsole designed specifically for Ugg Australia utlilizing the TC1 wet/snow compound. Repeating lug pattern maximizes surface contact and provides flexibility at the foot"s natural flex points. This boot features a leather bottom shaft with cuffed twinface top shaft. Shaft is about 7 inches tall. Exciting new colors coming for Fall 2010!