I don't think any of my paper shaper punches (which are so very very similar to our double punch) would go through 2 sheets of cardstock..
I did try to see if I could punch through a couple layers with my punch when I first got it but being that it was hard to even get more than one layer into the punch I abandoned the effort.
speaking of punches.. I love the slot punch - don't have it yet but played with my uplines, But after playing with it we decided we also need another slot punch with that slot going in the opposite direction! there were some ideas we had for the punch that won't work the way this slot one is going.. but anyways..
I am rambling now...
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