What is the difference between a stage one and stage two cold air intake?

A stage one cold air intake is typically a basic aftermarket upgrade that enhances airflow to the engine by replacing the factory air intake components with a more efficient design, often using a high-flow air filter. In contrast, a stage two cold air intake usually includes additional features such as a larger diameter intake tube and may relocate the air filter to a cooler area to further improve airflow and performance. Stage two intakes are often designed for vehicles that have other performance modifications, offering greater gains in horsepower and torque.