Dr. Elsey's Ultra Litter is the perfect solution to multi-cat households. It has medium grain clay consistency that is heavier in weight to prevent tracking outside the litter box. This results in an excellent clumping action before it reaches the bottom of the tray, and traps the smell of urine and odors. These clumps are tough and do not fall apart, preventing little pieces from being left behind when sifting. This litter is all natural and it is 99.9% dust free! Created with hypoallergenic ingredients and no plant proteins, it is ideal for both sifting and mechanical litter boxes.