An anodized fuel filter cap for the lower frame rail on your Ford 6.4L diesel! This cap comes in an assortment of colors and it works great with the factory oil filter. Has an external port that can be blocked off (hardware provided) or allow you to easily access the engine oiling system. This port could be used for measuring oil pressure or oil temperature, just to name a few! This cap fits well and looks great and is a major upgrade over plastic!