Million Mile Limited Warranty. Air Filter is Washable and Reusable. Replaces OEM Filter and Air Box. Works with OEM Computer Systems. Street legal in most states (Check specific CARB status). K&N starts with the largest conical shaped High-Flow air filter that will fit into the engine compartment while using factory holes and mounting points.. The filter is isolated from high engine temperature by a heat shield designed to lower the temperature of the air entering the engine, which increases horsepower. Next they attach the filter to a rotationally molded tube made from interlaced High Density Polyethylene. This process allows to precisely shape the tube to reduce turbulence and accelerate airflow into the engine. This is why the tubes have unique shapes or indentations that are specifically engineered for each application. Finally the tube is connected to the engine with adapters made from high strength materials such as silicon and reinforced nylon and ensures long life.