Pro 10R Filter Media: This filter features ten layers of pre-oiled cotton gauze media to provide maximum Longevity. Its progressive layering allows the filters to flow at high levels even when dirty, while its inverted top makes for more filter surface area, resulting in longer service intervals. This media is only available for select diesel truck applications. Pro 10R filters are easily recharged with aFe's POWER CLEANER and blue air filter oil. Rounded Deep Open Pleats: aFe POWER performance air filters use a rounded, evenly spaced pleat design which allows for more usable filter surface area, providing increased flow and greater dust holding capacity. Its surrounded by expanded metal that provides additional protection, preventing filter collapse and direct impact. 100% Polyurethane Base & Top: This aFe POWER performance air filter is constructed with a polyurethane base and top. Unlike other materials that degrade after repeated heat cycles in an engine bay, polyurethane maintains its original molded shape. Innovative Design: The Momentum series' patented interface uses a single clamp around the housing to secure the filter to the housing. This simple design allows for easy filter maintenance and replacement. Emissions Disclaimer: This product does not require a CARB EO#.