When you need clean, filtered, potable water, turn to the MSR® MiniWorks® EX Microfilter. This microfilter features AirSpring Accumulator™ providing filtration of up to 1L per minute. This microfilter removes unpleasant tastes and many chemical contaminants. This filter is perfect for day trips and extended hikes with a durable ceramic element and no tools required disassembly. The MSR MiniWorks EX Microfilter will keep you hydrated.
REVIEWS
197 Reviews
Andrew
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.
Chris
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
Al B.
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.
Mark J.
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!
Kevin (.
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.
Amy C.
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.
Steven W.
Worked great once I was shipped the missing hinge. Excellent customer service
Steve
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?
PatD
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.
william f.
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.
Lee
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.
JobJ
Hi. I've had this for over 5 years. It has worked amazingly well for me on my extended outdoor adventures. Recently, while cleaning it out I had a bit of an accident-i lost the small plastic ball that's at the top of the filter to prevent the backflow of water.
Sam P.
I purchased this pump for a 14 day backcountry elk hunt. The shear size of the pump almost completely deterred me, but I figured for the price and the usual MSR quality, I thought this was going to make everything just a little easier on my small group when it comes to getting water. Unfortunately, it became easily clogged on the first attempt in a clear stream. Even after cleaning (per the instructions) it never got any better. After three separate attempts, this pump stayed back at base camp for the remainder of the trip. Luckily I had my backup MSR trailshot and steripen, or things could have went bad.
Kaitlin K.
Great filter. Had the same one for 20 years and just got a new one.
Igor
We were on a hike in Adirondacks and once we went like ten miles deep in a trail we ran out of water. I literally pumped water out of the mud puddle.
Read All Reviews (197)
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