Keeps damaging particles from entering the engine and causing increased engine wear, Improves engine response time Protects the operational performance of your engine, Reduces ecological footprint through fuel economy, Boosts fuel economy by 6% to 11%, 98% Efficiency Against Rocks And Other Debris on the Road, Part Reference Numbers : 88077 XA4372 CA3901 AF3901 AF899 PA4372 A24372 46077, Kit Includes: 4x Air Filter, Kit Variations: K57-100120 K57-100535 K57-101114 K57-101419 K57-101799 K57-102179 K57-102559 K57-102939 K57-103319 K57-103699, Part Reference Numbers : 88077 XA4372 CA3901 AF3901 AF899 PA4372 A24372 46077