This is a hanger for a 3oz Brass hammer.
https://www.amazon.com/dp/B0058EDQ9K?psc=1&ref=ppx_yo2ov_dt_b_product_details
Requires the use of an empty insert from:
https://www.printables.com/model/152592-honeycomb-storage-wall
I printed it with supports sitting just like it hangs. I suppose it could be modeled a bit different to remove the need for supports, but I can't be bothered.
The author marked this model as their own original creation.