Tokyo Jujutsu High School Uniform button - Modded Loop

thingiverse

I was having problems printing the original model, so I modelled a slightly sturdier and larger loop. The top part of the button is exactly the same as the original. Even though your slicer might say there's some invalid geometry inside the button (I know I should've, but I didn't Boolean-Unite it to the parent part), once you print it, it prints nice.