Omega Paw Self-cleaning Litter Box Self-cleans by rolling to the right and back again Waste collects in the pullout scoop for quick and easy disposal No electricity or filters needed Controls dust and contains odors Ideal for big cats or multiple-cat households Ships in Certified Frustration-Free Packaging One year warranty How it Works: The Rolln Clean, Self-Cleaning Litter Box works best with clumping and silica litters. Simply roll the litter box to the right until the top touches the floor then roll it back to the upright position. Inside, a unique patented screen separates the clean litter from the clumped waste  putting all the waste into the scoop. Pull out the scoop and dispose the waste. Its that easy! Self-Cleaning Litter Box Brown Taupe Medium. Brown Taupe Medium. Cat Supplies. Approximate Product Dimensions: 18in x 18in x 20in (Length x Width x Height)