Hi,yes, I was just thinking that it looked like a cube with two opposite
corners cut off. I believe they call this chopping off corners as a
The only model I know would be David Mitchell's Columbus cube. I have made
something similar with business cards. You can adjust the diagrams to truncate
two corners instead of one.
Third picture from the top:
David Mitchell's book (Columbus Cube on front cover):
Diana (If David is on this list, I love your work!)