Safe Handcuff Toy

I figured it would be fun to design some handcuffs, but safe ones which can be opened quickly.
These handcuffs do NOT require any metal hardware to work. The cuffs are held together with the parts' own pins and are driven with a printed spring.
You only need screws if you plan on mounting these cuffs to something.
The cuffs have 4 5mm holes at the bottom for easy mounting.
When printed in PLA with good layer adhesion even a strong adult shouldn't be able to break these, please keep that in mind if you decide to use this for more than just a fidget toy.
At this point this is the 3rd major revision of this project (with some of the individual parts having received numerous sub-revisions).

Constructive criticism is very welcome as this project is still in development.