8 - Layer Oiled Cotton Gauze Dry Air Filter 'That's massive' is all you will hear about this 8 - layer oiled cotton gauze air filter that is included with the EVO7104C cold air intake system. This filter is uniquely designed to work with the Injen Twist - Lock System. Using our Twist - Lock technology has allowed our technicians to use the largest filter available for this application for maximum air flow and filtration efficiency. This giant air filter enhances the air volume resulting in increased power gains while making this installation process quick and easy.