Like having a fire extinguisher in your house or an earthquake kit, it's always better to be prepared. Although rare, a diesel engine runaway is caused when external hydrocarbons are drawn into the engine and can cause overspeeding and catastrophic engine failure. If this occurs, Life, limb and your vehicle are put in jeopardy. BD Diesel Performance has you covered should the worst happen with the BD 1036703-M Manual Positive Air Shut-Off (PAS) by cutting the intake air supply to the cylinders and safely shutting down the engine. The Positive Air Shut-Off butterfly valve design simplifies the number of parts and reduces the overall size as compared to competitive units and uses aluminum and stainless components plus weatherproof electrical connectors to prevent corrosion. There is no need for welding with the bead boot locks making an easy installation. CAC pipes are included for some vehicles.