The gasket on certain Audi and VW OEM engine water pump housings swells when it comes in contact with oil, causing the plastic housing to crack. This Dorman OE FIX housing has been upgraded to aluminum to prevent cracking. In addition, the gasket material has been upgraded to reduce swelling when it comes in contact with oil for a longer service life. This housing is designed to match the fit and function of the original housing on specified applications, and is engineered for reliable performance and durability.