This hook was designed to hang on water pipes in bathrooms so that brooms, or other stuff can hang nicely above the floor.
In Sweden (where I live) it is very common that water tubes run outside the walls in bath rooms, laundry rooms etc. This is very practical because one does not have to tear down the walls if a leak happens.
This makes it also as a suitable place to hang things. I am going to update this thing page here, with newer versions of the hooks - for different hanging positions and tube diameters.
Please check the name of the STL file to download the hook that fits your water tubes. You can also download the ZIP file with all the files inside - including the original CAD files.
(Since this page is a WIP, I'll delete the old files and update them with new ones below)
Download the STL file and print it with your favourite 3D printer. :)