Amazon.com: Air Filter Compatible with Honda Civic Si MUGEN Si 2.0L K20Z3 Eng Element : Automotive
Amazon.com: K&N Engine Air Filter: Increase Power & Acceleration, Washable, Premium, Replacement Car Air Filter: Compatible with 2005-2010 BMW (X3, X3 Si, Z4), 33-2372 : Automotive
K&N K&N Engine Air Filter: High Performance, Premium, Washable, Replacement Filter: 2006-2011 Honda (Civic Si, Element), 33-2343 in the Automotive Hardware department at Lowes.com
K&N R-1100 Universal Clamp-On Air Filter
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