I often bring home unwanted pet rats from the shelter where I volunteer. I think they make great pets, and I learned you can HOUSEBREAK rats. Really! This corner litter box is perfect. Put clay cat litter in it, "seed" it with a few rat turds, and there is a very good chance the rat or rats will begin to use it for both urine and feces. This keeps their cage clean much, much longer and they seem to appreciate the additional cleanliness. Rats are super clean little animals, and it's even better when they are housebroken to the litter box.