Different types of litter pearls is what I use in my cat-litter trays. You cant' imagine the difference in smell. Being a breeding male Taiga smells quite alot, but using litter pearls makes all the difference. I started using it in one (of four litter-trays) when Bissan had her kittens, now I use it in all four with great success. I will reccommend it to everyone keeping a breeding male!!