Effective Odor Control: Equipped with sunlight-activated charcoal, these replacement carbon odor filters effectively absorb and neutralize unpleasant smells, ensuring your home stays fresh Sizing & Quantity: Each pack contains four (4) round carbon charcoal-infused odor filters, each measuring 7.75" inches in diameter, providing a covenient supply of replacements. It is the perfect solution to cover up to a full year's worth of replacement filters - using one filter per quarter for hassle-free maintenance Durable Materials: Crafted from high-quality materials, these filters are engineered to maximize odor absorption and ensure proper ventilation of your pet’s litter box. Easy to Install: Simple and quick to replace, these filters are designed for effortless installation. First, remove your artificial planter and the florist moss. Then insert your filter by aligning the pre-made holes to the planter top Perfect Fit for Good Pet Stuff's Hidden Litter Box Planters: Designed specifically for compatibility with the ORIGINAL Round-Shaped version of the Good Pet Stuff Hidden Litter Box Planter, these filters maintain an optimal fit and performance.