Compatibility: This filter is designed for use with both the original Tommee Tippee Perfect Prep machine and the Tommee Tippee Perfect Prep Day and Night machine, ensuring compatibility with various models. Antibacterial Filtration: The filter features an antibacterial membrane designed to remove bacteria, impurities, and contaminants commonly found in water. This ensures that the water used to prepare bottle feeds is clean and safe for babies. Filtration Membrane: Inside each filter is a specialized filtration membrane that effectively removes bacteria, impurities, and other contaminants from the water, guaranteeing the quality of the water used for bottle feeds. Sterilized: The filters are sterilized and certified to food grade standards, ensuring their safety and suitability for use with baby feeding equipment. They should remain sealed until ready to be used to maintain their sterility. Long-lasting: Each filter lasts for approximately 3 months, depending on usage frequency and bottle size. Your Perfect Prep machine will notify you when it's time to replace the filter, ensuring continued effectiveness. Uniform Functionality: Despite potential differences in appearance, all Tommee Tippee branded filters function the same, providing consistent performance and reliability. Overall, the Tommee Tippee Perfect Prep Replacement Filter offers reliable filtration and peace of mind for parents, ensuring that the water used to prepare baby feeds is clean, safe, and free from contaminants.