K&N Drop In Air Filter Replacement E-1987 Fit For AUDI A3 A4 A5 S5 Q5 Quattro 2.7L 3.0L 3.2L 4.2L Designed to boost horsepower and rate of acceleration Can be cleaned and used again High air flow with exceptional filtration Lasts up to 50,000 miles before cleaning is required depending on driving conditions Works with original equipment manufacturer vehicle electronics