Amazon.com: K&N Engine Air Filter: Reusable, Clean Every 75,000 Miles, Washable, Premium, Replacement Car Air Filter: Compatible with 1999-2009 Honda S2000, E-2435 : Automotive
Part Number for air filter ring - S2KI Honda S2000 Forums
How to Change Engine Air Filter: 2005 Honda S2000 2.2L 4 Cyl.
changing engine air intake filter - S2KI Honda S2000 Forums