I needed a clip, and I was curious if I could make one using the elasticity of PETG, so I gave it a try.
Clip 2.0 Made with a 3D Printer
Things to consider when printing
To maximize the elasticity of the clip, it seems best to increase the number of wall lines and fill the interior completely with lines, as shown in the image above.
Since strong elasticity is needed, I recommend using PETG and setting the temperature high enough when printing.