The Litter-Robot 4 LitterHopper automatically dispenses fresh cat litter into your Litter-Robot 4, ensuring litter is at the optimal level for your cat's use. Say goodbye to another litter box chore with this hands-free solution to litter refills. Get time back and enjoy added convenience, whether you're home or away. Litter-Robot sold separately. This new product comes in black and is size 4.