Cap for Dodge, Ram, Jeep, Chrysler capless fuel system fuel cap. It is designed to fit snugly onto your fuel fill to help keep debris and moisture off of where it doesn't belong. It should fit most Dodge, Ram, Jeep or Chrysler vehicles with the capless fuel system although it will not fit all. This cap is approximately 3 1/8 " (80mm) outside diameter and 2 3/8" (60mm) inside diameter. This cap is designed as a preventative measure to keep unwanted debris out of your fuel system, it will not help to fix a check engine light due to an EVAP leak. This item is 3D printed out of a semi flexible rubber material giving it a tough reliable fit.