Quantum Pro 5R air filter by aFe Power is specifically designed for the Quantum Series cold air intake systems and feature an injection molded base and top for lighter weight and rigidity. The newly designed base includes a built - in, 3 - angle velocity stack for smooth, even airflow. The Quantum Pro 5R filter is a 360 - degree radial flow air filter with oiled, 5 - layer progressive cotton composite media that provides maximum flow, performance and protection. Captive screws are included to eliminate lost hardware and to securely fasten to the Quantum Intake system housing.