Polyurethane (PU) is a chemical compound that is processed in a special procedure into a coating or a yarn. As a coating, polyurethane is a type of paste, which is put onto the base material (for most of our wet weather clothing, a jersey made of polyamide). Total coating with polyurethane is very expensive (in comparison to coating with PVC) and for outer clothing, the best type of coating. And it is only this type of coating that guarantees a high level of water impermeability and good air permeability for breathability at the same time.