Large Five Layer Performance Air Filter: This 360-degree radial flow air filter features a 3-1/4" x 6-1/2" flange and our pre-oiled Pro 5R media with five layers of progressively finer cotton gauze media for maximum performance. It provides your engine with the largest amount of high-flowing air and delivers the highest power gains in most cases. This media is best suited for street use. Unique Sealed Housing: The one-piece sealed housing, constructed of XLPE (cross-linked polyethylene) polymer, is used to minimize the number of components and ensure the coolest air intake charge available. Dyno-Tuned Intake Tube: This system features a high quality, computer-designed, dyno-tuned intake tube to achieve maximum power gains while maintaining a perfect fit. Its XLPE material is heat soak resistant and extremely durable. Hassle-Free Installation: This is a direct fit intake system that utilizes factory mounting points and requires no cutting or modifications. All necessary clamps and hardware are included. Its revolutionary design uses half the number of parts of a traditional cold air intake system. Magnum FORCE Stage-2Si Cold Air Intake System w/ Pro 5R Media BMW X5 (F15) 14-18 L6-3.0L (t) N55 BMW X5 (F15) 14-18 L6-3.0L (t) N55