This was remixed from ThingiVerse so that it replaced a "Auveco #22705" clip that holds in the foot rest in a 2nd Gen Subaru Crosstrek. It should fit most 8mm holes for retainer clips.
I recommend printing in PETG on it's side with supports as seen in the second photo. I printed at .16mm and it seems to hold up well.
The author remixed this model.
Changed the length of the clip, made it thinner to fit the 8mm hole, and made the head smaller/rounded to blend in with the interior of the car.