I got this OTR tool for Detroit Deisel 2017-2020, I sold my truck and went local last year and i still got this thing.
it basically can do two things, forces a regen and clears codes. sometimes if you idle too much you'll get aftertreatment codes that can derate you but for whatever reason the truck won't do regen with the button, sometimes it won't even show it need a regen it just derates. u just plug this in and it forces a regen to start, then hopefully that takes off the derate. I used it a couple times, and it saved me a couple tow bills.