Omega Paw Self-Cleaning Litter Box, Pewter Self Cleaning Easy to use Takes no electricity, liners or filters Patented Grill separates clean litter from waste Easy Assembly.Please refer user manual attached below for instructions and troubleshooting steps. Large litter box self cleans by rolling to the right and back again Waste collects in the pullout tray for quick, easy disposal Effectively controls dust and contains odors Ideal for big cats or multiple-cat households Ships in Certified Frustration-Free Packaging