For use with all Tommee Tippee Perfect Prep machines. Anti-bacterial filter designed for use with water straight from the tap. The unique filtration membrane removes bacteria and other contaminants that can be found in water. Ensures your water is clean and safe to make a bottle feed, just like boiled water from your kettle. Each filter lasts up to 3 months* - We only recommend you use Tommee Tippee filters with the Perfect Prep machine. *Based on 6 x 260ml feeds per day