This is a fidget toy with a macaron appearance, and the cream filling clicky rotates.  It provides a soft-click sensation and can be rotated with just the fingertips of one hand. 

Customizable click feeling and case design you can choose from:

• Two types of wheels - normal or stiff (I recommend normal)
• Two types of case design - regular or for keychain

Assembly: 

1. Put the “spring” onto the “caseM” part.
    

2. Apply a very small amount of PTFE grease or similar to the inside of the “wheel” part.
 

3. Put the “wheel” on step 1 caseM.
 

4. Align the notches on both cases and snap-on the opposite side of the case. If printed with a properly calibrated printer, it should be possible to hold and smoothly rotate with the index and middle fingers.
 

Notes:

• Recommended layer height: 0.15 - 0.20mm, In my case with slicer, layer heights above 0.28mm, the spring, wheel clearance lost are do not function.
• This model may not achieve smooth rotation unless grease is applied to the inside of the wheel.
• Do not use Matte PLA, Silk PLA, as they have weak layer adhesion and can break with snap-on.