The 4-Pack Replacement Water Filters for all Models ZR-006 by ZeroWater are specifically designed for the Aqua Optima Evolve model. These white filtration cartridges are made of plastic and contain 5 stages of filtration including carbon/charcoal, reverse osmosis, and alkaline ionizer. With a capacity for 4 pack replacements, these filters are essential for removing contaminants from your kitchen water, ensuring clean and refreshing drinks for your household. The item dimensions of 8.50 x 8.00 x 9.25 inches make them easy to handle and store, while the included 4-pack guarantees long-lasting use without the need for frequent replacements.