Universal 2.5" Single Fan Fuel Saver Blue100% Brand New In Stock Single Propeller Design Horsepower Enahncement And Fuel Saving Capability Achieve Better Gas or Fuel Mileage Maxium Speed: 5,500 RPM Turbo Fan Intake Fuel Saver Spins w The Engine Speed While Generating A Maximum Force That Creates A Powerful Airflow Into The Combustion Chamber At High Speed. As Air Travels Through An Intake It Bounces Around Bends And Elbows In The House Causing It To Slow Down Pinning Air Can Be Less