AEM Induction Dry Flow synthetic air filters are designed to deliver superior filtration efficiency and dust trapping over oil-coated, cotton gauze filters. They feature an easy-to-clean synthetic filter media that does not degrade from cleaning like cotton gauze-type filters. AEM Induction Dry Flow synthetic air filters use a reinforced internal cage that is lighter and stronger than mesh types, a urethane body that will not shrink or crack like plastisol-based products, and an integrated velocity stack to increase the structural rigidity of the filler neck, all while improving airflow. They outflow most other brands with an impressive 99.4 percent filtration efficiency.