S&B devotes a huge amount of resources to engineer our intakes that allows your engine to run properly with stock calibration or enhanced tuning. The kit was designed to avoid check engine lights by maintaining proper airflow mapping of the Mass Air Flow Sensor. This kit comes with a massive, highly-efficient air filter which results in better performance and protects your engine. Available in either 8-layer cotton cleanable media, enclosed in a black powder coated steel cage for added protection. The OEM intake tube is small in diameter and highly restrictive. S&B's intake tube was designed with a huge diameter to allow for insane amounts of airflow to be fed to your engine. More airflow equals better performance. We use an innovative insert in order to get our gigantic tube to work with the MAF sensor parameters of a stock truck, removing this insert will cause your truck to drive poorly and possibly display a check engine light, as it will no longer conform to the stock calibration's desired MAF readings.