Description: The Audi Oil Filter Housing Seal (N-909-597-01) is a factory-spec O-ring or gasket for 2004–2015 Audi models equipped with 4.2L (A4/S4, 2007–2010), 5.2L, and RS4 4.2L engines. It seals the oil filter housing to the engine block, preventing oil leaks at this critical junction. A genuine Audi OEM seal built to original material and compression specifications.