Catgenie offers from Amazon.com

Cats use CatGenie like a clean litter box. Comfy Granules help cats dig and cover. For use only with the CatGenie Self Washing-Self Flushing cat box.
Price: $23.99 [Notify me when price goes down.]

Exclusively for cat-safe, hygienic cleaning of the CatGenie self-washing cat box (1 Cartridge good for 60 Cleanings).. CatGenie recommends at least 1 cleaning per day per cat. Cartridge lasts approximately 2 months for 1 cat - 1 month for 2 cats - 20 Days for 3 cats.
Price: $13.99 [Notify me when price goes down.]

Unique self-flushing, self-washing cat box maintains itself. Uses permanent washable granules that never need changing. Ideal for homes with 2 to 3 cats over 6 months old. Hardware, granules, cleaning solution, and instructions included.
Price: $255.61 [Notify me when price goes down.]