Check the listing for details. 4pcs replacement filter set for portable Reverse Osmosis with double DI filters.. Condition: New. Listed at 48.99 USD. {Title} My Aqua Filter 1 Universal Set (4 inline filters) for 5-stage Reverse Osmosis Systems, made in USA with double DI filters Item Description 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 K2555BB Omnipure DI Resin filter 5th stage: Inline H-F1035DI-33 filter: 2/3 of filter Nuclear Grade DI resin (made by ResinTech, USA) and 1/3 of Granular Activated Carbon T33 , made in USA. Replace the filters every 8-12 months. Shipping Shipping (US): We ship within 1 business day via USPS Priority Class Mail. Shipping (International): We ship within 2 business day via USPS International Priority Mail. Return Within 15 days. Customer is responsible for the shipping. Filters must be sealed and unused. Feedback Copyright , My Aqua Filter | All rights reserved.