The DNA air filter is a high-flow filter designed to fit in the factory airbox of the Nissan Skyline R31. It is washable and reusable, and is designed to increase horsepower and acceleration while providing filtration.
- Type: High-flow air filter
- Car model: Nissan Skyline R31
- Model years: 1985–1989
- Engine: 2.0 DOHC 24V Twin Cam
- Reusable: Washable
- Installation: In the factory airbox