Big Star's extremely lightweight snow boots are made of a combination of eco-leather and textile material. Inside insulated with a pleasant to the touch shoe cover. Velcro fastening. The Memory Foam System insole remembers the shape of the foot, ensures a proper fit, absorbs shocks and is resistant to deformation. The structure of the foam allows moisture to evaporate and regulate temperature. When choosing a size, please refer to the size chart.30-19/31-19,5/32-20/33-20,5/34-21/35-22 cm