The Mahle S42140.020 Piston Ring Set .020 is a high-quality OE ring set that is designed to maintain factory performance in your 6.7 Cummins 2007.5-2018. This set includes four piston rings that are made from a smooth, tough steel that is resistant to wear and tear. These rings have a protective coating that helps to extend their lifespan and keep your engine running like new.