Edelbrock Pro-Flo Replacement Air Filter #22906 is designed to deliver the right balance of filtration with limited restriction. It features synthetic media that delivers the right balance of clean air with the least amount of restriction. Made from a washable and reusable dry design that does not require oiling after cleaning. This combination makes it easier to use and maintain compared to cotton gauze air filters that depend on the right amount oil for proper filtration, without over oiling and fouling the MAF sensor.