The Culligan Better Water Replacement Filter is a high-quality filter cartridge with a capacity of 600 gallons. Made of carbon block material, this white filter is designed for under sink use and fits universally with the model D-40A. It utilizes carbon/charcoal filtration method for clean and refreshing water. Manufactured in the United States, this filter is suitable for improving the taste and quality of your tap water in your kitchen. Whether you are looking to replace your current filter or upgrade to a better option, the Culligan Better Water Replacement Filter is a reliable choice.