Perfect winter children's shoes from the Big Star collection. The upper for the ankle is made of synthetic material. In addition these boots have a Memory Foam System insert that remembers the shape of the foot which ensures a perfect fit absorbs shocks and is resistant to deformation. The structure of the foam allows moisture to evaporate and the temperature to be regulated. The boots also have a slightly stiffened heel. The rubber sole is nonslip. When choosing a size please use the size chart.2818/29185/30195/3120/3221/33215/34225/3523 cm.