Lip seals are among the most important seals in hydraulics and pneumatics. They are usually used to seal the cylinder at the piston or on the piston rod. They differ mainly in the geometry of the cross section. Symmetric lip seals can equally be used as well as a piston rod seals. Asymmetric lip seals, however, can either be used as a piston or a piston rod seal. The design, the material and the arrangement of the seals play a major role here and are adjusted according to the different requirements.