|The ETS Mitsubishi Evolution X 3.5″ Maf Housing with Velocity Stack. Made to replace your stock housing to allow more air flow for your high horsepower Evo X. Made with a 5″ wide velocity stack to allow the use of a larger filter for maximum air flow. Optional Filter & Coupler available. This is a critical component for making high horsepower on the Evo X. If your reaching .5v on your current setup, this is needed for higher air flow.