There's a reason the AIR4ORCE tunable intake system was named, 2012 Product of the Year, by Transworld Motocross magazine?Çöbecause it works.
The AIR4ORCE provides more horsepower by increasing the volume over a stock airboot and then allows you to tune the power delivery to suit track conditions or rider preference via interchangeable velocity stacks. There's simply nothing else like it out there, which is why you see it being run by many of the top racers and teams.