Puzzling

We found this adorable old puzzle made out of a NUT & BOLT!

This is the actual puzzle - it's so cool!

The trick involves holding it by the threaded end and turning the nut, instead of turning the head (I don't know why it makes a difference but that's the trick.) It is super easy to undo BUT to put it BACK together was hard! So I'm not undoing it again...not even to take a photo to display (sorry.) And it's cute this way so I'm leaving it alone.