MiniWorks® EX Microfilter

  • MSR MiniWorks EX Microfilter
  • MSR MiniWorks EX Microfilter
1 4

MSR

MiniWorks® EX Microfilter

$129.95
$129.95
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The best-selling filter on the market, delivering long-lasting, fully field-maintainable water filtration.
  • Testing: Meets NSF protocol P231 for removal of bacteria (99.9999%) and protozoa (99.9%) from beginning to end of filter life in “worst-case” water.
  • Reliable: Durable carbon/ceramic element ensures safe, taste-free water—even with frequent, heavy use.
  • Field-maintainable: Can be cleaned repeatedly for full filter recovery with no tools required.
  • Fast Flow: AirSpring Accumulator™ increases filtration speed; up to 1-liter per minute.
  • Better-tasting Water: Carbon core removes unpleasant tastes and odors caused by organic compounds, such as iodine, chlorine, and pesticides.
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Description

The MiniWorks EX microfilter is the worldwide best-selling microfilter, delivering long-lasting, field-maintainable water filtration in demanding environments. Engineered for frequent and heavy use, it utilizes our workhorse Marathon™ EX carbon/ceramic element to ensure clean, reliable and taste-free water. Thanks to its innovative AirSpring Accumulator™, it’s capable of pumping one liter per minute and the flow rate can be renewed easily and repeatedly in the field—no tools required. It’s lightweight and compact and, most importantly, been proven reliable by thousands of adventurers just like you.

Tech Specs

SKU:
14006
Weight (Standard):
1 lb
Weight (Metric):
0.46 kg
Width (Standard):
2.75 in
Width (Metric):
7 cm
Length (Standard):
7.5 in
Length (Metric):
19 cm
Height (Standard):
5.5 in
Effective against bacteria:
Yes
Effective against chemicals/toxins:
Yes
Effective against particulate:
Yes
Effective against protozoa:
Yes
Effective against viruses:
No
Filter media:
Ceramic Plus Carbon
Filter pore size (microns):
0.2
Flow (L/min):
1 liters per min
Flow (strokes per liter):
85
Cartridge life:
2000 liters
Field cleanable:
Yes
Field maintainable:
Yes
Water Bottle Adapter:
Yes
Cartridge replacement indicator:
Yes
Material(s):
Ceramic
Country of Origin:
Made in the U.S.A. of U.S. and Imported Materials

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FAQs and Documents

Can I upgrade my old MiniWorks with an EX filter?

Marathon™ EX ceramic cartridges are compatible with all WaterWorks and MiniWorks microfilters, old and new. Using it in a pre-2003 filter will increase a MiniWorks filter's output by approximately 25%, thanks to the new AirSpring Accumulator™.

What are the materials in the EX filters?

The Marathon ceramic element is made from diatomaceous earth that's heated to the point where it just begins to melt. Most particles are caught within about .005 inch of the surface. When it clogs, you abrade away the clogged pores, making them immediately ready for more use, with almost 100% recovery after each cleaning. Marathon ceramic provides long-lasting protection from protozoa and bacteria. A block carbon core reduces tastes, odors, some chemicals, and many pesticides. The WaterWorks microfilter also incorporates a PES (polyethersulfone) membrane filter, which passes the test for a sterilizing or pharmaceutical-grade filter. It serves as a safety net, providing a second fail-safe seal.

How long will my ceramic filter last?

How long a filter lasts will vary radically from one water source to the next. The ceramic element can last up to 2000 liters. Filter-life ratings are based on best-case scenarios because the testing is performed with clean lab water. Generally you can assume that your filter will last between 50 and 100% of the rated life.

How much water will my filter pump before clogging?

Normal conditions may allow a user to filter between 10 and 20 liters between cleaning. Please note that water quality varies a lot with the season and water source. In general, the more turbid (cloudy) the water, the more frequently your filter will require cleaning and eventually replacement. The MiniWorks is one of the most cost-effective portable treatment devices currently available.

Why is the handle on my filter so hard to push?

There are three possible causes of this. The most likely is that one of the microfilters is clogged. Review the instructions for cleaning the ceramic filter. The PES membrane (WaterWorks microfilter only) may also be clogged. It will have to be replaced or removed altogether. Lastly, the piston O-ring may be very dry, causing friction. Lubricate it with the silicone lubricant provided in the maintenance kit (or use lip balm or petroleum jelly).

Why is the handle on my water filter so hard to pull?

If the handle is hard to pull, something is obstructing the flow of water into the filter. Clean the inlet foam and remove any kinks in the inlet hose.

Why does the handle on my filter feel limp when pumping?

The most common reason for a limp handle is dirt under the umbrella valve. Remove the head of your water filter to expose the umbrella valve. Rinse under it or pull it off and rinse. Reinstall.

Why does my filter squeak when I am pumping?

The squeaking you hear is probably caused by actuation of the pressure-relief valve. This valve is designed to release when there is excessive pressure. Water goes back out the intake hose so you stay dry. You can tell if your relief valve is releasing by watching bubbles in the intake hose—if they go back and forth when you pump, the relief valve is working. It may be time to clean your ceramic filter (reference your owner's manual for complete details), or maybe you are pumping too fast. Do not pump faster than one stroke per second for best efficiency. Older MSR filters sometimes squeak in the pump head, piston pins, and bushings. You can eliminate the squeak with a tiny dab of lubricant on these parts. Newer MSR filters have the lubricant molded right into the pins and bushings, eliminating the squeak.

How should I store my EX filters?

Remove the ceramic element and air dry for 3–5 days. This will prevent growth of mold, mildew, and bacteria. Wash and dry other filter parts thoroughly before long-term storage.

I forgot to dry out my filter before putting it away—what should I do now?

The ceramic cartridge, which comes as standard equipment in the WaterWorks and MiniWorks, can be boiled to kill bacteria that may grow in it. Always let the water cool down before removing the ceramic cartridge from the water. Removing it early can damage the plastic end caps. (Cold water can be added to the hot water to speed this process.) Dry thoroughly before storing. FYI: Because the WaterWorks microfilter has a bacteria-proof membrane immediately downstream from the ceramic cartridge, bacteria cannot get into the water you drink even if it grows in the ceramic.

What happens if my filter freezes?

If you anticipate that you will encounter freezing temperatures, make sure you drain the filter of excess water after each use to protect it from damage. If the filter does freeze, bring it inside the tent or other warm place to thaw, or follow the directions (in the instructions) for boiling the cartridge.

Can I use the Sweetwater® Purifier Solution with the MiniWorks?

Unfortunately, no. The SweetWater Purifier System and Solution are regulated by the EPA and have undergone extensive laboratory testing to verify their efficacy as a system. SweetWater Purifier Solution is carefully formulated to inactivate viruses remaining in water that has been pumped through a SweetWater Microfilter. Filters vary in performance and it is likely that more or less disinfectant may be required to achieve purification with other filters. Along the same lines, for the solution to work independently of a filter, you would need a very strong dose—to the point of tasting offensive. The wait time would also be much longer than five minutes. Finally, cryptosporidia, which would have been removed by the filter, would not be effectively inactivated by use of the SweetWater Purifier Solution alone.

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We Believe in What We Build

At MSR, we take pride in engineering the highest-quality outdoor gear available, and we stand behind everything we make. MSR gear is built to be exceptionally durable and easily repaired. And we back it up with the best service in the industry, all to keep your gear performing for you—and out of landfills. Visit our MSR warranty page for more info.

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Overall rating: 3.978355 / 5 from 231 reviews.

AI Generated Review Summary

The MiniWorks® EX Microfilter is highly regarded for its reliable water filtration system, especially for long trips. Customers appreciate its clean water taste and ease of maintenance. However, some users have noted issues with the filter's capacity and flow rate.

Summary topics

  • Flow Rate: 4%
  • Long Trip Effectiveness: 5%
  • Filter Capacity: 5%
  • Pump Reliability: 8%
  • Water Taste: 7%

Review topics: [size, model, performance, problem, quality, looks, design, packs, durability, results, equipment, works, build, service, features, filter, water, pump, taste, cleaning, flow, msr, liter, system, trips, use, miniworks, buy, maintenance, bottle].

Review highlights

  • "Small price for clean great tasting water for cooking and drinking." — Wayne A.
  • "No one is sick, water tasted great, and I’m glad to see this product still on the market!" — Mark J.
  • "The device is light enough, fast to clean filter, and easy to maintain." — Jeff D.

Reviews

Left me high and dry twice

"Purchased two of these about 3 years apart as you always should have a backup. I go backpacking in some remote places as I guide hikes every year. Last year, one of these filters stopped working and was pushing water back out the inlet. I've dismantled, cleaned, maintained per all instructions with no luck. I sent back under warranty, which was a terrible process, and took them back out this year. Both broke again, the same way, same problem. I had to boil water full of mosquito larvae for two days to make it by. I wrote a long letter to the manufacturer, as the MSR book that comes with the filter says it is a lifetime warranty, but Cascade Designs, which dba MSR only gives you a 3-year warranty. One filter is only 2 years old and has filtered less than 20L of water, the other less than 100L. I never got a response back. Super disappointed in quality, communication and service all around. I went and bought a Katadyn filter yesterday. Will not look at MSR again."

— Nate M. (1/5)

The Best. Period.

"The best portable water treatment system on the market, microbiologically and practically. Under-promises and over-delivers, time after time."

— Dan V. (5/5)

Built to last.

"I’ve had my filter since ‘93. Took to Banff and to Baffin Island and a Louisiana hurricane. ( we lost power and water for a week). Still working without an issue. Oh btw so is my WhisperLite never change a part. Can’t say the same for fuel bottles. I seem to loose them."

— P G. (5/5)

I have a vintage SweetWater Micro Filter

"I bought this likely 30+ years ago, the pump has a PN# 32-788, it has ben dry stored all this time. It has only been used once. Can I recondition the filter as per instructions (16-24 hours in 1oz/1ltr bleach solution) or has this filter reached its use by date? If it needs to be replaced, can you direct me the correct model number of the replacement filter to order. I now live in New Zealand, and if you recommend a NZ supplier, that would be a bonus. Thank you"

— Dougie (5/5)

Has Lasted 32 Years

"It was bought in 1992. Used on one camping trip then and stored until now (2024). Looks and operates like brand new except the tubing is slightly discolored from age but no big deal."

— Capt M. (5/5)

No problems, easy to use.

"No problems, easy to use."

— Jayne T. (5/5)

Great filter

"I purchased this filter back in 2011 or 2012. I was introduced to them in Boy Scouts (as a leader) and purchased one for my own and family backpacking treks. I still use the original filter and cartridge although considering replacing the ceramic cartridge. I'm sure I have surpassed the 2000 liter mark by now. I have never had a problem with my filter. I drain and clean it after every trek. During treks if I filter murky water, I do clean it the best that I can in the backcountry and dry it out. I recommend this model to my clients. I have had issues with other brand filters clogging and being tricky to use, especially in low flowing water sources, but not with this filter. It's great for small group filtering."

— Susan T. (5/5)

Filter Frequence

"Just received my MSR filter for my expedition next week, looks great and durable. I only have a question about the filtration speed; the description tells 1 liter per minute. When I tested the filter after the first cleaning I only got 200-300ml per minute, maintaining the pumping frequence of 60-70 strokes a minute. Am I doing something wrong, or is this normal when using the filter for the first time?"

— Dirk (3/5)

Perfect!

"I have had and used this filter extensively while backpacking over the last 25 years (yes, I still use the original one). It has provided a family of four with enough clean water for drinking and cooking, during weeks at a time. It is slower when the water is murky, but it still works, and when too pluggeg, it can be cleaned on site. I gave my brother one when he started backpacking and it was very hard to pump, so he followed the instructions to take it apart and back together, and it worked perfectly after, so try that if needed ;-) Just carefully follow the cleaning and maintenance instructions, and you’ll pass this down to your grandchildren!"

— Caroline (5/5)

25 years and still going great

"I purchased my miniworks back in 1998 or 1999. Used it with no issues while working for a summer camp for a couple of years. Life took over and have been vehicle camping for years where I could take fresh water along. Fast forward to June 2024. Did a short notice 3 day hike and pulled the filter out of storage. Gave it a test the night before leaving and was having issues....but, I followed the field maintenance tips and BOOM, worked like a dream. Had no issues during the trip and was very happy with the performance! Will keep this filter as long as possible!! Thanks MSR."

— Andrew (5/5)

Q&A