Tested and proven to remove contaminants to deliver fresh, clean water Reduces chlorine and improves water's smell and tasteReduces chlorine and improves water's smell and taste: Tested and Certified by NSF International against NSF/ANSI Standard 42: Tested and Certified by NSF International against NSF/ANSI Standard 42 For best performance, change filter every 6 months or 300 gallons, whichever comes first