We use whatever is "sand"like and is on sale - typically tidy cats. We have a regular litter box with a spiral staircase inside with a cover - it looks like an igloo. Ody is solid so little boxes are too cramped for him. This is what it looks like in brown:
Amazon.com: Booda Dome Cleanstep Cat Box, Brushed...
On top of the Tidy Cats, Chad uses Arm & Hammer (I think??) Cat Odor control. If Chad hasn't cleaned it in 4 days (K;MN"@ELK) then it starts to smell, but not before then.