Collapsible expandable pump design ideas

I dawned on me the other day that it should be possible make a penis pump that is collapsible. It would be great for those who travel and want to take the pump for the ride (or flight). I suppose this could be made with graduated cylinders that link up together, but I imagine there is a type of plastic available that could easily crush a bunch of ridges to become almost flat and then expand to become a fuller size. Of course the plastic would have to stay rigid enough to maintain the pressure needed for some solid pumping, so maybe my first idea is not the best.