I designed a snap lid to be used with the box from the Cascade Platinum dishwasher tabs. The original lid that comes with the box is very flimsy and has a weird split design, which makes it hard to reuse. The 3.8 L box, on the contrary, is very sturdy, and I wanted to be able to reuse it for storage. This 3D printed lid is designed to fit it snugly and features snap tabs that grab the snap collar on the box.
I was looking for a watertight case to store a bunch of 3.5″ hard drives. The idea was to protect the off-line backups from water damge in case sprinklers get activated in the building. It was decided that water or dust damage was a more likely threat than fire, so the solution did not have to be fire safe.