Find Your Store
Home Page

Cart, contains 0 items

When autocomplete results are available use up and down arrows to review and enter to select. Touch device users, explore by touch or with swipe gestures.
Expert Help
Earn Rewards

MSR
MiniWorks Ex Water Filter

4.185393258426966 out of 5 stars
178 Reviews

Temporarily Out Of Stock

Don't get too bummed. This item is on the way and will be available for purchase as soon as it rolls into the warehouse.

Can't wait? Consider one of the other Water Filters & Purification we have in stock.

View Similar Products

MiniWorks Ex Water Filter

Filter your water year after year with the MSR MiniWorks Ex Water Filter. Clean this lightweight, compact filter back to like-new condition, without any disassembly tools. The MiniWorks' ceramic element ensures long-lasting protection against bacteria, protozoa (including crypto and giardia), and particulate, and the carbon core removes yucky tastes. MSR's little wonder (7.5 x 2.75in) can filter up to 1 liter per minute. As a bonus, the MiniWorks Ex Water Filter screws onto a standard Nalgene bottle or any MSR dromedary bag.


Details

  • MSR's best-selling micrfilter known by backpackers for longevity
  • Marathon EX carbon/ceramic element ensures clean, tasty water
  • AirSpring Accumulator delivers one liter of water per minute
  • Field cleanable without any tools
  • Includes filter, hoses, stuff sack, hose float, scrub pad, and instructions
  • Made in the USA of US and imported materials
  • Item #CAS0479
Purifying Element
Marathon EX (carbon/ceramic)
Eliminates
particulate, bacteria (99.9999%), protozoa (99.9%), chemicals, toxins
Filter
Marathon EX (carbon/ceramic)
Pore Size
0.2microns
Cartridge Life
~2000L
Action
AirSpring Accumulator (pump)
Flow
1L/min
Field Cleanable
yes
Includes
filter, hoses, stuff sack, hose float, scrub pad
Dimensions
2.75in x 7.5in
Claimed Weight
1lb
Activity
backpacking, camping, paddling trips
Manufacturer Warranty
limited 3 years

Overall Rating

4 based on 178 ratings

Review Summary

1 Stars - 21 reviews
2 Stars - 5 reviews
3 Stars - 6 reviews
4 Stars - 34 reviews
5 Stars - 112 reviews

What do you think about this product?

View

Selecting an option will reload the available reviews on the page
1 out of 5 stars

June 2, 2024

First time fail

Bought to replace old Katadyn. Never able to use even once. Took from box and hit the trail. Went to use and missing hinge pin. Can’t even find anyplace online to reorder. Disappointed

Chris
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

5 out of 5 stars

January 24, 2024

Good filter but you have to keep it clean

Bought several years ago, my not be a full liter a minute but close. I did find that i needed to take it apart and lube the o rings, and the antisyphion valve was folded over from the factory. That resulted in poor proformance out of the box. I used lip balm( beeswax based) to lube the o rings and it works well. If you have multiple bottles to fill, you may have to clean the filter while doing so. That simply means the filter is doing it job. Drain the water from the filter after use, good time for another scrub of the filter. I have used the gravity bags and will use them in camp, but who wants to carry 6l of water on their back. To be honest i have never gotten the rated number of gallon/ liters from a gravity filter, always clog up even with back flushing and very clean river/ stream water. Have a maint kit on hand, and a spare filter for long trips, as well as a back up filtration system. With a little TLC this is a great filter.

Al B.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

5 out of 5 stars

November 6, 2023

20 YEARS LATER!!!

I bought this product in 2004 to hike part of the Appalachian Trail. Now older with young kids that want to camp I pull this thing out (always cleaned and dried after previous uses) and it worked flawlessly. No one is sick, water tasted great, and I’m glad to see this product still on the market!

Mark J.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

5 out of 5 stars

August 15, 2023

Algonquin Park

Its light, packable, fits wide mouth Nalgene bottles. Worked great for 6 day trip into the interior. No issues just clean water. I recommend this product. FYI purchase and prepare a backup filter just in case.

Kevin (.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

1 out of 5 stars

August 2, 2023

Dissapointed

As many others here have written, this filter worked fine for the first couple of times that I used it, however it seems that the filter is clogging very quickly even when filtering clear river or lake water only. The pressure builds in the canister so much that you are just pumping water back out of the hose, or the system seems to fail and will not pump up any water through the hose at all. Took almost 20 minutes to pump 1/5 litre of water! This filter failed me in the middle of a backcountry trip this week and I had to boil water the rest of the trip. This is very disappointing and frankly dangerous to bring as a source for clean water! Do not recommend and I would appreciate MSR refunding my purchase.

Amy C.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

4 out of 5 stars

July 17, 2023

Great Product

Worked great once I was shipped the missing hinge. Excellent customer service

Steven W.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

2 out of 5 stars

June 10, 2023

Unhappy with product

I have had 3 MSR mini-ex water filters in the last 15 years. My first filter- I used perhaps for 15 trips. I didn't have much issue with my first one- I figured it might be safer to get a replacement since I didn't remember how effectively I kept the filter clean while in college :). It was getting old and didn't seem to be filtering as effectively, my wife bought me a new one about 4 years ago. My second filter the pump (just 4 years old) The plastic piece that holds the handle to the piston just fell off (and I couldn't find it) in the middle of the trip. I never got around to trying to find a new piece and just ended up buying a new filter because the first MSR filter worked fine. I figured perhaps it was my fault- maybe I bumped it against something? I still have this 2nd filter because I figured then I had replacement parts if needed for the future I then bought ANOTHER filter just last year. I used it only twice in northern MN, in very clean (at least to the eye) water source. I honestly have probably only pumped 15 L through the thing. I used in a lake that was crystal clear. The middle of the trip the filter stopped pumping water through. It took me an hour to pump a nalgene. I tried to clean the line/look at the filter but couldn't identify the problem. I'm really frustrated with the product. Both of them let me down in the middle of trips. I still have both filters but not sure I can trust these moving forward. I have followed everything to a T on the instructions the last two filters I have had. Fortunately I brought a back up Sawyer this last trip. I almost never leave a bad review on anything- very frustrating though to be on trips twice and have them break. I am not an avid backpacker- I use the pump maybe 1-2 times a year. I would be interested to hear response from MSR about possible warranty coverage for my concerns?

Steve
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

2 out of 5 stars

May 9, 2023

Don't waste your money.

I purchased this filter in 2021 and used in on three weekend trips. On the first trip it worked flawlessly. On the second trip is was a pain but it provided adequate water for our group. On the third trip we couldn't fill a single nalgene bottle. All of the maintenance was done pre and post trips and we always used clear lake water off shore. I used this style of pump filter for years as a kid, they should bring the older models back.

PatD
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

5 out of 5 stars

May 2, 2023

this is a back up

this is a back up for a unit that I have been using for over 15 years straight to filter all of my water, the original is still going strong but now I have a back up too, its a great product and you can bet your life on it.

william f.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

4 out of 5 stars

April 8, 2023

Well made and effective

Had mine for 20 years. Great product. Cons- Unless water is fairly clear, you can find yourself removing the cartridge and scouring the surface clean every 2lts. Pros - easily maintained and well made, better that than something with a faster flow rate that eventually slows and you can't do anything about it in the field.

Lee
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site