Aquasana drinking replacement filters, powered by Claryum Filtration Technology, use a unique combination of activated carbon, ion exchange and sub-micron filtration to force your water, under pressure, over almost 2.9 million square feet of purification media to achieve incredible contaminant reduction and still maintain the healthy minerals you need. Our selective filtration technology significantly reduces chlorine, chlorination byproducts, lead, cysts, pharmaceuticals, herbicides and pesticides, Volatile Organic Compounds (VOCs), Synthetic Organic Compounds (SOCs) and gasoline additives, among others, all while maintaining minerals like calcium, potassium and magnesium. The AQ-4035 is NSF certified to standards 42 and 53. Only the genuine Aquasana AQ-4035 replacement water filter set is guaranteed to be compatible to replace AQ-4025 filter elements in all Aquasana drinking water filter systems, including AQ-4000, AQ-4500, AQ-4501, AQ-4600 and AQ-4601 models. Replacement filter cartridges last six months.