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Sears UltraFilter RO System Filters ®

Sears UltraFilter RO System Filters ®

* Sears Kenmore UltraFilter, Whirlpool, EcoWater and Ecodyne ® compatible replacement water filters and RO reverse osmosis membranes.

Sears Kenmore * UltraFilter 150, 625.385700, 42-38476

Sears Kenmore * UltraFilter 300, 625.384720, 42-38476

Sears Kenmore * UltraFilter 350, 625.385720, 42-38476

Sears Kenmore * UltraFilter 500, 625.384750, 42-38476

Sears Kenmore * UltraFilter 550, 625.385750, 42-38576

Whirlpool WHER 12 Reverse Osmosis System

Whirlpool WHER 18 Reverse Osmosis System

  1. Regular Price: $39.99

    Special Price $29.99

    As low as: $15.99
    WFO-500 - Sears Kenmore Ultrafilter ® 150, 300, 350, 500 & 550 reverse osmosis system compatible replacement water filters twinpack (one pair). Replacement for Sears item #04238476000 model #38476. Compatible replacement filters for the Sears Kenmore UltraFilter ® Reverse Osmosis Drinking Water Systems # 38570, 38472, 38572, 38475 and 38575. Prefilter and post filter both included (two filters total). Also fits: Whirlpool ® WHER 12 & WHER 18, part #WHERF K002-87, EcoWater ® Compatible Carbon Block Water Filters. Sears Kenmore UltraFilter ® 150, 625.385700, 42-38476 Sears Kenmore UltraFilter ® 300, 625.384720, 42-38476 Sears Kenmore UltraFilter ® 350, 625.385720, 42-38476 Sears Kenmore UltraFilter ® 500, 625.384750, 42-38476 Sears Kenmore UltraFilter ® 550, 625.385750, 42-38576 Filters should be changed at least every 6 months. Order extra filter sets and save even more. Learn More
  2. Regular Price: $99.99

    Special Price $75.00

    As low as: $40.00
    WFO-536 Reverse Osmosis Membrane TW30-1810-36 Sears Kenmore UltraFilter ®, Whirlpool ®, EcoWater ® Compatible. UltraFilter 150, 625.385700, UltraFilter 300, 625.384720, UltraFilter 350, 625.385720 (7267962), Whirlpool Wher 12 (#7264223) compatible reverse osmosis membrane. EcoWater Sears Kenmore UltraFilter ® 150, 300 & 350 compatible. Learn More
  3. Regular Price: $99.99

    Special Price $75.00

    As low as: $40.00
    WFO-550 Reverse Osmosis Membrane TW30-1810-50 Sears Kenmore UltraFilter ®, Whirlpool ®, EcoWater ® Compatible. UltraFilter 500, 625.384750 (#37233557), UltraFilter 550, 625.385750 (7267970), Whirlpool Wher 18 (#7266186) Compatible Reverse Osmosis Membrane. EcoWater Sears Kenmore UltraFilter ® 350 & 450 compatible. Learn More
  4. Regular Price: $36.99

    Special Price $19.99

    As low as: $12.63
    Stainless Steel Insert Flow Restrictor - Custom made from 303 SS Stainless Steel. This is the finest insert flow restrictor availble from anyone, anywhere. Includes heavy duty 303 SS sediment pre-screen to prevent debris from lodging in the flow chamber. If you like insert flow restrictors, you will love this one. Learn More
  5. Regular Price: $8.99

    Special Price $5.99

    As low as: $3.99
    WFO-O-ring - Sears Kenmore UltraFilter ®, Whirlpool ®, EcoWater ® , Ecodyne ® compatible o-ring. Fits Sears Kenmore UltraFilter ® 150, 625.385700, 42-38476 Sears Kenmore UltraFilter ® 300, 625.384720, 42-38476 Sears Kenmore UltraFilter ® 350, 625.385720, 42-38476 Sears Kenmore UltraFilter ® 500, 625.384750, 42-38476 Sears Kenmore UltraFilter ® 550, 625.385750, 42-38576 Sears Kenmore ® 42-38456 Single Stage Deluxe Whirlpool ® WHER 12 Reverse Osmosis System Whirlpool ® WHER 18 Reverse Osmosis System, EcoWater ® 350 & 450. #E1000-228 --- 2 1/2" Diameter. Be sure to order Dow 111 Silicone Sealant to help prevent leaks. Learn More
  6. Regular Price: $5.99

    Special Price $3.99

    As low as: $1.79
    Dow Corning/Molykote ® 111 6 gram O-ring Silicone Lubricant and Sealant - 6 gram pillow pack. (like a ketchup packet) Great O-ring sealant and lubricant. FDA and NSF approved. (Do Not Use Petroleum Jelly As It May Break Down O-rings Or Housings) This is the same premium grade silicone sealant and lubricant used in underwater photography cameras, scuba gear and other underwater applications that simply can't afford leaks. Why not use the best for your reverse osmosis or drinking water filtration system?

    Dow 111 Silicone MSDS Safety Sheet

    Learn More
  7. Regular Price: $7.99

    Special Price $5.99

    As low as: $3.49
    Pro Products Sani System Sanitizer. 0.25 or 0.5 fl. oz. concentrate. Sani-System ® Pro Products is proud to introduce Sani-System, the first and only EPA product approved for sanitizing water softeners, RO units and Water Coolers. Sani System is proven to kill 99.9% of E. coli, E. coli O157:H7, Staphylococcus aureus, Listeria monocytogenes and other harmful bacteria. It does not use chlorine, other oxidizers or acids that can harm water softener equipment parts. Use is simple; each dose comes in a pre-measured pouch. Just cut, pour and regenerate softener. No measuring, No mess! Sanitizing Equipment! Applications Interior Surfaces of Water Softeners, Reverse Osmosis (RO) Units, Ice Machines, Water Coolers, Water Holding Tanks and Pressure Tanks. Sani-System is now NSF certified!This is the best sanitizing solution available anywhere! Stock up and save. Learn More
  8. Regular Price: $34.99

    Special Price $19.99

    As low as: $14.99
    Replacement Non-Air Gap Pure Water Faucet - Calif. Low Lead Level. Has one single tube connection. 7" high. Long reach - Extends 5 1/2" from center of faucet. Learn More
  9. Regular Price: $49.99

    Special Price $37.99

    As low as: $17.99
    TDS Meter - Tester. The Only Way To Know If Your Reverse Osmosis RO Membrane Is Performing Correctly - Tests for TDS - Total Dissolved Solids. A Must For All RO System Owners. Compare Incoming Feed Water To Treated Water - Replace Membrane If Less Than 80% of TDS Is Being Removed - The lower the TDS level in the water, the more efficiently your body's cells actually get hydrated by the water that you drink. The higher the TDS levels in the water, the greater the probability of harmful contaminants that can pose health risks or hinder the absorption of water molecules on the cellular level. Simple to use for Reverse Osmosis membrane monitoring. We really like this tester and think that anyone who wants to know about the quality of their water should have one of these TDS Meter Testers to monitor their RO membrane. Learn More
  10. Regular Price: $49.99

    Special Price $39.99

    As low as: $19.99
    TDS Meter - Dual Mode - Installs Inline - Check the TDS level with the push of a button. Now you can easily check to make sure the water from your reverse osmosis system is top quality. Measure the tap water coming in vs. the purified water going out of your system at any time. Very easy installation. FEATURES Displays TDS levels of the feed water and product water with in & out electrode probes. Highly efficient and accurate due to its advanced microprocessor technology. Auto-Off function conserves battery power. The unit shuts off automatically after 10 minutes of non-use. Comes equipped with John Guest Quick-Connect T-fittings as shown. Installs quickly and easily. SPECIFICATIONS Range: 0-9990 ppm Accuracy: ±2% Always know if your RO membrane is performing correctly! Learn More
  11. Regular Price: $79.99

    Special Price $49.99

    GGN-Tank-4 - 4 Gallon RO Reverse Osmosis Tank 1/4" NPT Threads. Stainless Steel connector. This is the perfect replacement tank for most residential RO Reverse Osmosis systems. 7 psi Choose White or Blue color. UPC #850901003491 Learn More
  12. Regular Price: $24.99

    Special Price $17.99

    As low as: $12.99
    Air pressure gauge for reverse osmosis water accumulator tanks - Specially calibrated for reverse osmosis system tanks. Scale from 1 to 20 PSI. Large scale reading over small PSI range allows optimum accuracy. Just like car tires lose air pressure, so does the bladder of your reverse osmosis water accumulator tank. Improper tank air pressure will cause your system to operate improperly. This is a must for all reverse osmosis system owners. Learn More
  13. Regular Price: $27.99

    Special Price $17.99

    Protect the bladder of your tank by using our tank inversion stand. Most tanks hold the water in the top portion of the tank instead of the bottom. Storing the water on top of the bladder adds the weight of the water to the pressure to cause unnecessary stress on the bladder. By inverting (turning upside down) it removes the weight of the water on the seal where the bladder is attached to the inside of the tank. Fits most standard 3 and 4 gallon tanks. Plastic Inversion RO Tank Stand. UPC #850901003408 Learn More

Easy TDS Membrane Performence Calculator
See If It is Time To Replace Your Membrane

Simply enter your Feed Water TDS and RO Water TDS into the boxes above and click "Submit". The percentage of TDS (total disolved solids) rejection will be displayed. We normally recommend membrane replacement once you drop below 75%. This may vary in areas with high TDS in the feed water.   Let the tap water and reverse osmosis water run for a few seconds before drawing your sample.

See our selection of TDS meters under Water Tests.  Knowing the rejection rate is the only wat to know if it is time to replace your reverse osmosis membrane.


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.


* Sears UltraFilter ® is the registered trademark of Sears UltraFilter, the manufacturer of Sears UltraFilter ® brand water treatment equipment.  The replacement filters and membranes listed above are not manufactured or endorsed by Sears UltraFilter.  Rather, these filters and membranes are manufactured by other companies.  While these filters and membranes are compatible for use in Sears UltraFilter ® brand water treatment equipment, we make no representation as to whether using these filters and membranes is consistent with the warranty and specifications applicable to Sears UltraFilter ® equipment.