The Ezi-LockOdour Extra Absorbent Pads are designed to be used in conjunction with the Ezi-LockOdour Dual Layer Cat Litter System. The pad is placed in the slide-out tray at the bottom of the litter system and it works to immediately absorb and lock away both liquid and odour. The pad is quick and easy to change and because you simply dispose of the liquid filled pad, you won't have to scrub litter clumps off the tray. This Extra Absorbent Pads are design for multiple cats or large cats.