US Made. Total filters: 4
1st stage: Inline Sediment Filter 2"x10" 5 Micron, Made in Taiwan. 2nd stage: Inline Granular Activated Carbon T28 Carbon Pre-Filter 2"x10", NSF Certified, made in USA. Membrane (not include in package - change every 2-3 years).
4th stage: Inline DI Mixed Bed Filter 2"x10", NSF Certified. Made in USA. 5th stage: Inline Omnipure Granular Activated Carbon T33 with 1/2 lbs KDF-55 media, 2"x10", NSF Certified, made in USA. Replace filters every 6-8 months.
Replacement filter set for Countertop Universal 5-stage Reverse Osmosis Revolution RO Purification Water System with DI Deionizing Mixed Bed 0PPM and KDF-55 postfilters (without membrane)