Hydronix 5 Stage RO Reverse Osmosis Water Filter Replacement NSF 14 Filters 1-2 yr SupplyThis 14 filter bulk pack delivers one to two years of complete RO maintenance for any standard 5 stage reverse osmosis system, with every component NSF certified by Hydronix for universal compatibility. You get four sediment filters, four UDF carbon filters, four carbon block filters, and two inline post filterseverything except the membrane. SPECIFICATIONS Complete Annual Filter Supply Sediment Filters 4 Filters 5 micron, 2. 5" 10" UDF Carbon Filters