Genuine OEM Audi power steering hose seal, part number 420422389D. This seal is designed to provide a secure, leak-free connection within the power steering hydraulic circuit, preventing fluid loss under high pressure. It is positioned at the connection point of the power steering line as shown in the assembly diagram. Engineered with specific material properties to resist hydraulic fluid degradation and thermal stress, this seal maintains system pressure. Genuine OEM seals are critical for steering system reliability, ensuring that hydraulic connections remain tight and free from leaks over the service life of the vehicle.