Large selection of replacement water filters, reverse osmosis membranes, testing kits and water filter system repair parts. From one water filter or membrane to case quantity discounts.


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DuPage Reverse Osmosis Water Filters ®

DuPage ® Water Conditioning Under Counter Reverse Osmosis Drinking Water System Compatible Replacement Water Filters, Reverse Osmosis Membranes, DIY Service Parts and HELP Guides.

DuPage RO-TS3C-10 Reverse Osmosis System

DuPage RO-TS3T-24 Reverse Osmosis System

DuPage RO-TS4T-24 Reverse Osmosis System

Be sure to check our Parts Department for important parts such as TDS Testers For Reverse Osmosis Membranes, Replacement Tanks, O-rings , Filter Housing Wrenches, Faucets, Pumps, Fittings, UV Systems and more parts for your reverse osmosis pure water filtration system.   View maintenance and servicing tips online at our Installation & Trouble shooting Guide.


* DuPage is the registered trademark of DuPAge, the manufacturer of DuPage brand of under counter drinking water system filtration equipment.  The replacement water filter cartridges, reverse osmosis membranes, water tanks, faucets and repair parts listed above are not manufactured or endorsed by DuPage  Rather, these replacement filters, RO reverse osmosis membranes and replacement parts are manufactured by other companies.  While these replacement water filters, repair parts and reverse osmosis membranes are compatible for use in DuPage under counter reverse osmosis water filtration equipment, we make no representation as to whether using these water filter cartridges and RO reverse osmosis membranes is consistent with the warranty and specifications applicable to DuPage under sink drinking water system equipment.