But what can it do?

It's easier tbh, you pretty much just smash a moebius loop

 

It has two sides that you can see at one, but when you fold it up, a third side appears and one of the previous two disappears into the fold pockets - and also, if you swish it around enough, the sides turn around, like in my initial pic, the circles on the corners were initially drawn in the center

Yeah, I found it at vihart :))

 

but then I found mathematische-basteleien.de which explained it in-depth

That's cool I made one in high school