A fidget for the contest. The black case is 25mm square, so it's small. Attached profiles are for Bambu Lab ABS, but should work just fine if you switch to PLA.

Assemble both cases as shown below.

Place the gear into the top assembly and the spacer plate onto the bottom. The gear will be snug and spacer may nee some mild persuasion.

as show below. the pins are slightly different sizes so check before you force it on :D. adjust the arms as shown fully in and full out.

now carefully flip one side over making sure you have the pins aligned properly and place it gently and make sure the arms are still correct and press firmly until its fully seated.

Have Fun!