【Compatibility】: 5" Filter Back Exhaust Compatible with 2007-2012 Dodge Ram Cummins Diesel 6.7L (No Muffler). 【Material】: Made from heavy duty aluminized steel, with more efficiency and durability. 【Practical equipment】: Improves fuel economy by 1-2 MPG, delivers a rich, mellow exhaust. 【Non-mechanical installation】Very easy to install right in your own garage, no instruction needed, install with common hand tools. 【Superior service】: If there's anything we can do for you, please feel free to tell us. If you receive no response, that may be filtered by Walmart system, please check your Trash Box or sign in your Walmart account to check the message page.