Here is a non-electric cat litter box that saves you time and effort cleaning after your pet. The VARLNALY Self Cleaning Litter Box has a fully enclosed pull-out design. It can accommodate pets up to 22 pounds. It comes with a high density activated carbon filter cotton and self-closing lid to keep odor contained.
The base is 7.78 inches deep to prevent litter and urine from leaking. You can find out more about it here.