I wanted coat hooks a bit like, but the code wasn't to my liking, so I redid the programming. The code is fully customizable online to allow a very wide range of designs.
The mounting works with just one screw and hides the screw when mounted. The screw hole is nicely designed so it snap fits very tight (see instructions).
The STL's named "Knob_XX_XX.stl" are the ones I used to print my coat rack, the examples are just to show some of the different possible forms.
The default settings are for a 4xN flathead wood screw. If you have significantly different screws you might need to adjust the screw settings.
The model is rendered frontside down, so you should be able to print the knob without any support material when not using a to big rounding around the knob.
The screw hole has 45 degree angled slopes that both help grip the screw better, but also make het hole printable without support. If you do print with support material, make sure the angle is at <45 degrees so you don't get support material in the screw hole, which is hard to remove.
To mount a knob you can use any ordinary drywall or wood screw. You can use a wall plug or just directly screw in the wall, depending on the material. Leave the head of the screw sticking out ~4mm. Try on the screw and adjust the screw if needed. The knob should slide on ~3mm relatively easy and then get tighter as you pull down. This is a bit of balance you have to find, but I have mine so that it takes about 5-10kg of pulling force to snap them on.