PETKIT PURA MAX Replaced Cat Litter Pad, Waterproof and Leakproof Replacement Litter Mat, Scratch Resistance, High FlexibilityReplacement Cylinder Mat: Replaced cat litter pad for PETKIT PuraMax self cleaning cat litter box. Made from excellent physical property material, this replacement cylinder mat is scratch proof,waterproof and anti stick. Item Size: Approx. 16 X 15. 7 X 0. 8 inch Easy To Replace: 1. Please empty remaining cat litter inside before you replace the litter pad; 2. And then take out the filter screen; 3. Remove the previous litter pad from the under buckles