The Peritas Cat Pads are designed to be used in the Tidy Cats Breeze Litter Box. They are made of high-quality plastic and are tested to be one of the most absorbent cat pads on the market. With activated carbon technology, these pads can absorb and control urine odors for up to one week for a single cat (3 days for two cats). The leak-proof design ensures that they will not leak when placed in the litter box.