This replacement engine coolant reservoir is manufactured from quality materials to withstand the stresses of underhood heat and engine vibration. It is engineered and manufactured to match the fit and function of the original part. This part is compatible with the following vehicles. Before purchasing, enter your vehicle trim in the garage tool to confirm fitment. [Audi A4 Quattro: 1998, 1999, 2000, 2001] - [Audi A4: 1998, 1999, 2000, 2001] - [Audi A6 Quattro: 1998, 1999, 2000, 2001] - [Audi A6: 1998, 1999, 2000, 2001] - [Audi Allroad Quattro: 2003, 2004, 2005] - [Audi RS6: 2003, 2004] - [Audi S4: 2000, 2001, 2002] - [Volkswagen Passat: 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005]