These light-weight aluminum dough proofing/retarding pans are stack-able and easy to fit into your fridge.
Each pan holds one dough ball and you put put them in your fridge to let them sit overnight, letting the dough develop some flavor. The pans stack so that each one is sealed by the one on top. You only need a pan cover for the top pan in your stack.
When you're ready to use the dough, you can carry them out in their pans and the doughs out one at a time, leaving the others sealed below so that they don't dry out, and if you're cooking in an outdoor oven, you can keep dust, leaves, pollen, and other airborne life-forms from dancing on your dough.