BlueFall’s NSF-certified MWF refrigerator water filter upgrade reduces contaminants like mercury, toxaphene, dichlorobenzene, carbofuran, alachlor, benzene, lead, cryptosporidium, and giardia. This filter upgrade will provide you with healthier, purer water, that tastes amazing. NSF Certified NSF International is an independent nonprofit organization that examines consumer products to ensure they comply with strict standards for certification. By analyzing product materials, observing manufacturing facilities, testing products repeatedly and monitoring product development, the NSF serves as a safeguard for consumer safety. The BF-GE-MWF is NSF certified. What's In The Box Four BlueFall MWF SmartWater replacement refrigerator water filter.