Ring clip resists accidental opening

Note, this uses a trivial amount of support. (I don't know if it's necessary, but this is such a quick print, and the support usually comes off when the print is taken off the bed anyway.)

I made this in OpenSCAD for measuring spoons that had cheap rings that kept opening up, but it could be used for other purposes such as to fasten a tag to an object or hold punched sheets of paper or cardboard together.

To close the ring, the spade-shaped end is inserted into the receiving loop point first, and then flattened down to snap it shut. It has a high resistance to being pulled apart, but can be opened easily by bending it to reverse the process of snapping it shut.

The measuring spoons that are thus connected have been used, thrown in the sink, gone through the dishwasher, and replaced in the drawer several times with no opening, whereas the original rings had an annoying tendency to open up and spill the spoons all over every time they were used.

I didn't have a photo so I used the render view in OpenSCAD.

OpenSCAD is a free download. Even without knowing how to code in it, you could modify the variable assignments at the top of the file to modify it somewhat:

bandHt = 2;
bandWd = 2;
bandID = 50;
fThick = 2; // 'offset' used for female thickness
ringGap = 22.5;
surfaceHt = 0.3;
claspHt = bandHt + 1;

I've also done some simple rescaling in PrusaSlicer.