HoppScotch.bun Bumbox Deluxe Rabbit Litter Box, Extra Large 21.45" Training Cage with Toilet Tray for Small Animals, Pink

https://a.co/d/0bjizT6V I have this one and it’s great. I was worried my bun wouldn’t like the gridding or it would hurt his feet but he immediately got into it and seems to like it. He naps in it a lot lol. It also helps make clean up a bit easier and I can change the litter box a lil less often than I used to. I always put a liner on underneath the gridding so all I have to do is remove the top, tie off the bottom, and toss it. My only gripe is the holes are a bit small and don’t allow all the hay and poop and other stuff to go through, but I’d rather have that than bigger holes that do hurt his feet. I just have to transfer a bit of hay and poops that didn’t fall through into the tray below when I change it.

I've used the Bumbox and really liked it. It has bigger holes in the corners for better pee drainage.

That's a generic cheap grate, a very fine grate with 1mm spaces won't have be that one. But if you want the poop to fall through, you'll have to accept a few tiny drops might still cling to him or give up the concept of grate entirely. "the problem will only be marginally improved since it is still bare plastic so it will still cause him to be standing in pee, just less of it." Overall a plastic grate with evenly spread holes isn't that bad, there won't be that much pee for him to stand in. So just a generic plastic litter box with a grate, that has a removable tray or case in it would be good enough, I'd think. The tray is then filled with any thing of your choice, including easy to use puppy pads that come in sheets.