Freight car storage box

I have more freight cars than the Welztalbahn can take, so I want to rotate cars on and off the layout. So far I used a deep drawer under the layout and stacked cars in there. Naturally, finding a specific car and keeping it with its car card proved challenging over time, so I rarely changed cars. Today I did an experiment with a box from the "this could be useful in the future" stash.

This is basically a pizza box. I cut the walls from a corrugated sign board, hot-glued them into the box, and used regular kitchen towels for some padding. The shelves are a bit too narrow for my new car cards and the box is somewhat flimsy. Nevertheless, I hope this will serve its purpose well.