The Polaris Ultraweb high performance air filter was co-developed by Polaris and Donaldson to create the highest performing air filter for this vehicle. It uses Donaldson exclusive Ultra-Web® Nanofiber Filtration Technology which offers a higher initial efficiency compared to standard cellulose media and has very high efficiency throughout a filter’s life. Provides superior engine protection with 99.99% efficiency. Superior dust-holding capacity and 20% increase in service life over the stock air filter. Lower restriction over gives you better performance for high horsepower, torque, and acceleration.