I'm selling a little used Cold Air Intake system, compatible with 2005-2006 FORD: Excursion, F250, F350, 77-2570KTK.
This actually works, but I sold the vehicle it was used on shortly after I got this intake system, so it was used for less than 100 miles. I can say it does improve engine power, of course I have no way to measure that.
I got it on Amazon, this is their listing: https://a.co/d/078iPGyb