In addition to all the benefits offered from Catrine Cat Litter, Catrine Premium Extra is a perfume free, compact cat litter, especially developed for a multi cat home.It has an anti-bacterial affect and is made from micro bentonite (a natural product of clay) that expands when wet, absorbing several times its dry mass.The benefit of clumping litter is that you only need to throw away the used parts, conserving the rest of the tray, making the litter last longer and saving you from buying so often.Each box of Catrine can last your cat up to six weeks!