Why RAM Cummins 2500 fill tube leaks diesel when fueling

We found this in our supply closet of truck parts. This item can be shipped worldwide. The seller is onlinecamerasystems and is located in this country US. This is in what seems to be the original factory packaging and only has the transfer tube.

How To Install An Adjustable Fuel pressure regulator

Includes a bracket, nuts, bolts and washers that can be used to mount the FPR to the brake reservoir bracket on a 2g. Dsm ie-fpr kit with aeromotive fuel pressure regulator extra fittings are included to cover different mounting preferences. I’ve seen cheap FPR’s that do not rise at a true 11 ratio, some are finicky to adjust, some leak.