Hollow NF Membrane Water Purifier Features How Hollow NF Membrane Water Purifier Works 1, Permeate Selectively 2, Pure physical filtration by feed water pressure 3,Crossflow filtration, automatic washing and minimal fouling. The service life of hollow NF water purifier is more than 5 years. 4, Space-saving installation, easy to use, no waste water and no electricity required. Hollow NF Membrane Direct Drinking Water Features 1, Purer water contains desired mineral solutes: Ca, Mg, Fe, Zn, Sr, etc. 2, Remove viruses, bacteria, heavy metal, chemical residues, etc. 3, Water quality is weakly alkaline, small molecular clusters