Greddy's AIRINX air filters kits are made with a special dry element that is placed between their new dual chrome ABS spiral cages. Greddy's double-ply element uses 2 layers of 3 dimensional urethane foam to increase filtration and maximize intake airflow. The inner layer is made up of a fine foam while the outer ply has large openings. more details on - https://www.carid.com/greddy/airinx-small-air-filter-mpn-12500301.html