For 2009-2013 Audi A4 2.0L K&N Performance Air Intake System +13HP! 69-9505T | eBay
Amazon.com: K&N Engine Air Filter: Increase Power & Acceleration, Washable, Replacement Car Air Filter: Compatible with 2000-2013 Audi/Seat (A4 Cabriolet, S4, RS4, A4 Quattro Cariolet, Quattro, Exeo), 33-2209 : Automotive
K&N Engine Air Filter: High Performance, Premium, Washable, Replacement Filter: 2015-2018 AUDI (A4, A4 Quattro, A5, A5 Quattro, A5 Sportback, Q5 II), E-0648" - Walmart.com
Air Filter, Performance (K&N) for B8 A4-A5-S4-S5 or Q5-SQ5 w/ 3.0T, 3.2L, and 4.2L
K&N 69-9505T Performance Air Intake System
K&N Typhoon Air Intake for 09-10 Audi A4 2.0L | eBay
KandN | Shop for KandN Filters and Cold Air Intakes Audi a4 b8 (2009/2016) 2.0t quattro Parts – UroTuning
K&N Air Filter Audi A4 1.6L/1.8L/1.9L/2.0L L4 / 2.4L/2.5L/2.7L/3.0L V6 – Redline360