Wow!

That's a neat idea. I have splat mats* under both my litter boxes, but I like your box idea much better. I don't think I really have the room for it, though. I must think about this. GREAT idea. Thank you for sharing.

* The large one is sold to be under children's high chairs, the small one I made from a torn shower curtain... I can lift it and the litter goes back to the center of the mat where I can sweep it easily.