Dude, I don't know. But I know Thats how they work because I have one. The springs stretch, they don't compress, there is no space between the spirals for them to compress. How does it work? You would have to ask Byron.
I posted a pic when I first got it (I think it's in the who sells... section) you can see them there. They physically cannot compress. It is not possible.
But it's a rad machine!

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