We call it the Pioggia shoe cover, and although the name is Italian for ?rain,? that doesn’t really capture the essence of this bootie. Sure, it´s completely waterproof, with sealed seams, a waterproof zipper and a silicone-sealed top edge to keep water from entering. we´ve backed the PU-coated fabric with fleece to make this bootie warm in the coldest conditions, while the high stretch also gives it a close, comfortable and aero fit.