This is a spare tire bumper extender for a Jeep Wrangler TJ tailgate. (Mine is a 2002, but I believe this will work for most TJ models).
It is a spacer for the spare tire bumpers if you have changed the rim offset or tire size so that the bumper will still contact the spare tire to support it and keep it from bouncing around.
This requires longer bolts and re-use of the factory bumpers. It is just an extension to sit between the tailgate and the factory bumper.
The model is 26mm tall, but it is likely that you need a different size spacer. Just use your slicer to cut off the bottom of the model leaving the length you need.
The top of the model has a small fillet around the screw hole to allow for the factory bumper which likely as a small bulge.
I printed them in on a Bambu X1C in TPU95 at 75% infill and they came out with similar squishiness to the factory rubber bumpers.
I have included a step file in case you want to play with the model.
The author marked this model as their own original creation.