Very Hard Expander

They say it's manly if you can stretch five springs.
It's a health device, so I kept it thinking I might use it someday,
hesitating to dispose of it,
and stored it carefully at home.

I plan to ship it with simple packaging over this box.

You can attach and detach the springs with hooks.
Please adjust the resistance and use it.

I don't know the details, so please refer to the photos.
Thank you.