Antibacterial filtration: The filter removes impurities, contaminants and bacteria. Standard water filters don’t include an antibacterial filtration membrane, so won't remove bacteria Compatible: Designed for use with all Perfect Prep machines  Know when a fresh filter is needed: Your machine will let you know when to fit a fresh filter. The original Perfect Prep machine has a warning light, and the Day & Night machines shows a message on the screen No need to use pre-boiled water: For added convenience water passes through an antibacterial filter to ensure it's clean and safe, just like boiled water from a kettle Prime before first use: Prime in cold water for at least 5 minutes before first use to remove air bubbles and any loose particles and ensure complete filtration