are 4-lobe seals that maintain the advantages of symmetry and dimensions typical of O-rings but can also be used in dynamic applications and have very low friction, and consequently minimum wear at low pressures, and no torsion.
are metal washers with a trapezoidal elastomer element (NBR or VITON) vulcanised on the inside diameter. The sealing function is performed by the elastomer and the metal ring has the task of containing the deformations due to the pressure of the system.
are available in NBR, VITON, EPDM, NEOPRENE and SILICONE. For silicone, red, white and neutral colours are available.