In case of dust or watertight sealing of an application, EPDM, Silicones or other types of rubber are often chosen as the material for the seal. However, for many applications a good seal is only possible if the material already seals with a very low push back force (CFD) to the construction. It is also possible that the variation in the gap to be sealed may have a large gap variation due to tolerances in the construction. In these situations, a High Performance Polyurethane seal can provide a solution. Due to the very low push back force and one of the best compression sets this material is often a better solution than the conventional materials.