Exactly Ron, You're Articulated at Better Than I Did.

On the aluminum one, you can see that it has the most amount of ability to flex right there at the center. The other one is reverse that kind of hinges. Those triangles are attached in the center and it the terminal of the cell is around the inside. So it hinges from the inside of the cell to allow that crimping action to happen and allow that to kind of fold down and over.