Compatibility: Cat Litter Box Replacement Filters for Litter Box Cat, Activated Carbon Charcoal Filters for Hidden Cat Litter Box Highly Effective: Effectively adsorb urine and fecal odors, keeping your home smelling fresh Standard Size: Length: 7.8inch; Width: 7.8inch; Thickness: 0.4inch. Depending on the size, you can also use it on your other for Hidden Cat Litter Planter Pack of 6: We offer a 6 pack of cat litter box replacement carbon filters , each individually sealed in a bag; we recommend changing the filter every 1 month which provide 6 months of filter for your hidden cat litter box Easy to Install: There is no need for any tape, just the carbon filter can beplaced inside these 4 screws to hold it securely Color: Black Material: Sponge Package Contents: 6pcs * Cat Litter Box Replacement Filters Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.