The EziLockOdour Dual Layer Litter System is an innovative new litter tray designed to reduce litter box odours in your home! Natural zeolite pellets dehydrate and drain liquid onto an absorbent pad below the tray, which in turn locks in the odour. Cleaning is a breeze as there are no wet litter clumps to scrub from the bottom of the tray.simply remove and replace the pad once weekly. Solid waste can be scooped from the top and a complete litter change only needs to be done once a month!