Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:5240561.

I saw this puzzle on YouTube and decided to try recreating it in Fusion 360. I think it came out well. Unfortunately, I would rate the difficulty of this puzzle at about 1 on a scale of 5. If you have 30 minutes and 8 seconds to kill, you can print this puzzle in about 30 minutes and then solve it in the remaining 8 seconds. Enjoy.

I find the puzzle works best if the fit is a bit tight the first time you fit it together. I tried to size the elements optimally, but FDM printing being what it is, your results may vary.

Print two copies of single.stl or one of pair.stl. The parts are the same.