Horsepower and torque gain will vary depending on vehicle
iNJEN Pre-FilterThis accessory for Injen air filters prevents the filter from becoming saturated if splashed by water and mud. When used in dusty conditions it can also extend the filter cleaning interval by filtering and keeping much of the dirt from the air filter. Features:    Treated to be water repellent    Protects the air filter from becoming saturated when splashed    Extends filter cleaning intervals in dusty conditions by filtering and keeping dirt from the air filter    Stops small dirt particles without creating restriction    A Pre-Filter is available for most Injen air filters    Made in U.S.A.Injen TechnologyÕs Hydro-Shield Pre-filters are race proven material manufactured from highly durable polyester. Uniform micron openings allow the filtering of debris .005Ó or larger. The Hydro-Shield Pre-filters are factory treated using an embedded hydrophobic process which offers consistent airflow water repellency and maintains horsepower gains.