RacingLine Billet Oil Filter Housing Audi B9 S4/S5/RS4/RS5/SQ5WHY CHANGE? Tired of staring at your cheap, brittle plastic oil filter housing every time you lift your bonnet? Us too, and thats why weve come up with our beautiful billet Oil Filter Housing to replace it. Its made to match OEM dimensions right down to the original factory size hex nut. The Filter Housing accepts the factory engine oil filter to maintain simplicity and keep that OEM fitment for your future oil changes. A quality part means you can