The plugs are designed to replace failing pressure relief valves.
Additionally, the plugs seal in 30,000 psi rail pressure and helps improve engine starting.
For Dodge, the available engines include 2007-2012 6.7-liter and 2003-2007 5.9-liter CR.
As for Chevy, the available engines include 2004-2010 6.6-liter.