The Whirlpool UltraEase reverse osmosis replacement pre/post filter (WHEERF) should be replaced every 6 months to keep the system working efficiently and to ensure the highest quality water is available for your family. This system is NSF certified and built in the USA. All Whirlpool under sink drin...

Whirlpool — WHEERM Reverse Osmosis Replacement Membrane NSF Certified Contaminant Removal Our WHEERM Reverse Osmosis Replacement Membrane fits our most advanced filtration systems that meet the requirements set by the National Sanitation Foundation (NSF). The NSF Standard for water filtration system...