I redesigned the original “IGRARING” for extra flexibility, the additional hole in the circular section allows for easier opening and closing while the internal slit provides the needed flexibility due to material compliance. The original is technically too stiff to print in PLA (Ideally it should be printed in PETG) however this remix allows for PLA without issues.
There's slightly less interference between the fitting portions of the model (mainly due to the compliant nature of the slits / holes) which means there's less engagement making it easier to pull apart by hand but it is strong enough once closed.
As a bonus it uses less material and prints faster.
For other sizes you can just resize the model and play with the model height for more or less engagement (taller means more surface area = stronger clip). Resizing makes sure the entire model is proportional to the required stress and load, however thinner versions could be made of course by modifying the model.
This is not necessarily better than the original, just my own take.
If there's enough interest I could make a parametric version next.
SLICING: Make sure your seams are not within the clipping mechanism otherwise it's going to be super stiff at first. Printing with lower layer heights will provide a smoother click action, but dynamic height is preferred all around.
Ideal for room temperature uses, haven't tested in a wide range of temperatures but we all know PLA is not the best candidate for extreme temperature ranges anyway.
The author remixed this model.