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The MSR MIOX Purifier w/Batteries represents a revolution in water treatment. This 7 x 1in purifier fits into your back pocket and requires no pumping, no iodine or nasty chemicals, and no maintenance. You simply add water, shake, press a button, and voila, you have up to 4 liters of great tasting, purified water. How the heck does the MIOX Purifier work? An electrically-charged chemical-reaction kills bacteria, viruses, giardia, and cryptosporidium. * Includes two CR123 Lithium batteries, salt, safety-indicator strips, instructions, quick-reference card, and storage sack.

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I got it for the end of the world..

    Hey, it may be sooner than later at the rate we are screwing things up.

    Do I want to drink water with this bleach solution in it? No.

    Do I use it much if ever? No.

    If the poop ever hits the fan and I need it is it available? Yes.

    I prefer to use a filter and then a steripen to kill anything that might make my butthole explode for days on end.

    It is cool to play with and have a little science experiment in pen form. Plus, when the poop does hit the fan you can render that poop harmless to drink.

    Sweet little purifier

      I'm feeling pretty positive after my first trip with the MIOX. It's pretty easy to use after you read through the instructions and fits all my needs. Plus it doesn't take up much space in the pack. I'm not a fan of how the water tastes though. Kind of funky and like drinking from a pool, but I got used to it after a couple hours.


        Lite & easy. Never gotten sick and never waited 4 hrs for anything. Almost 2 years ago went on a 10 day'r with lady friend and she is paranoid about getting sick from water after Mexican water ruined her vacation there the privious year. She had a pump filter and a U.V. pen and we used the same water sources, she got sick on day 9 with the works, you know, jumping behind a bush every 50 yards. Over a week later, she was fine. Hiking the desert and South we drink from some pretty nasty water sources and maybe I have a cast iron gut or this thing works really well.

        foreign travel-local produce!

          Here's a killer suggestion. If you make a solution that is twice as strong as the directions suggest you can use it as a fruit and vegetable wash. We've done this with stuff we bought in the markets in south america and yunan china and so far have not gotten sick eating local produce. Of course don't drink the solution.


            It only takes about 20 minutes to prepare solution for up to 4L liters of water. It is easy to use and cheap to maintain. You only need to replace the PH strips, salt, and batteries. This is much cheaper than any filteration system and even most ultraviolet systems out there. It is also super light weight and great for hiking.

            Excellent Purifier

              This is a light and easy purifier..used this as one of our main water treatment applications for a long trek in and out from GII bc in Pakistan, and it worked extremely well. Liked that the water tasted "clean" and that it was a fast, simple, and light system to use. I would order the extra salt package available for longer periods of travel to ensure that you don't run out. Highly recommend this product- when every ounce counts, this wins on weight to performance ratio, and we definitely put it to the test in areas and environments where there was a lot of fluctuation in temps, and exposure to foreign bacteria.

              handy, but..

                I like this product; it's small and very easy to use, and awesome for traveling in places where you want to treat the water from the tap. In the backcountry, I guess I prefer a pump...I found the taste of the water we treated with this to be overly chlorine-y. We might have been overdosing it, though. At any rate, I'm glad I have it, and continue to use both methods depending on the needs.

                Stellar performer

                  I've been using this for several years (since it first came out) mainly in the Sierra-Nevada. It has never let me down in any way. It's light, it's easy to use, and it works.

                  I know I can rely on the treated water from this beauty wherever I am. What more could I ask from it?

                  Awesome but bad in COLD weather.

                    Very useful but had trouble with it couple of time but had it replaced under warranty with no question asked... But now as I look back, I think it was due to the extreme cold weather (Aquamira tablets would work best for this situation).

                    Love this as AT hiker in decent temperature when I've treated my water frequently but I have mailed it back to home as I've stopped treating my water with an exception for when it rains (I do uses Aquamira for that).

                    Better than UV lights

                      I have been using this purifier for a few years now and ran into trouble on a trip where temps where hovering in the low teens. I had a hard time making the brine solution required for the chemical reaction with the cold water. I also had a problem with my original battery in the low temps. My friend was carrying the UV light treatment device and it worked fine but he needs 4AA batteries which makes his much heavier. This is great for mild weather, tastes fine, and is super light. I still trust it more than anything else on the market because the water you treat will treat anything it comes into contact with. Therefore, one can shake the bottle to treat the inside and flip it over with the lid partially unscrewed to treat the threads and cap on your watter bottle. For this reason it's much more trustworthy than the UV light options even if you have to wait 30 min to drink the water after treating.

                      the best

                        This purifier is the best ive had. It uses electricity to basically create clorine from salt to put in the water. It works great, is about the size of a mini-maglight, is incredibly light, and even though it uses clorine it doesn't make the water tast bad. The only draw back is that since it is not a filter it does not remove silt from cloudy water. It is great for clear water from rocky streams or lakes. If you want to go fast, light, and compact this is the filter. If you backpack through areas with silty/cloudy water, I suggest the MSR miniworks.

                        Easy, light weight, reliable, GREAT!

                          I've used these professionally for the past 4 years. Whether on a personal jaunt or guided trip, the Miox is simple and light weight. It is similar to iodine in that you need to wait for the ionized solution to treat your water, but it's treat a go unlike a pump. So stop, fill, treat, and 20 minutes down the trail go ahead and drink. Battery life is affected by the cold- and the batteries aren't easy to find so if you're traveling off the beaten path you may want to think about extra batteries or another system. Otherwise, I carried 1 set of batteries and treated enough water for a group of 10 for 12 days.

                          group camp champ

                            I took a group of 10 boys into the Sierras for a 3 day trip. Most of the boys had not had any previous camping experience so I knew we were going to use a lot of water. The MIOX worked very well for making large quantities of water in preparation for cooking and setting up for small hikes. The one side effect that I ran into was the taste of chlorine that would build up in the bottle after approx 5 refills. This is not a problem for cooking because it boils off real fast. On the second trip we used the MIOX for all of the cooking and cleaning water and alternated MIOX and ceramic filtering for drinking water. The combination worked very well. The MIOX works great as long as you plan ahead. The ceramic filter is better if you want a small amount of water quickly. I will be using this filter from now on whenever I go out with a group of 3 or more. It is small, durable and can purify as much water as you have storage for.


                              I bought one of these a few years back because it was so small. You can pare down the unit so that the kit will weigh about 4.25oz. But it takes a while to purify the water...not a big deal when you're at camp, but a pain when you're in the midst of hiking. The entire process takes about 10-12 minutes and you might have to do it twice (or more) times before it is purified. It comes with test strips that tell you if you were successful, so there is no guessing. Definitely check out the SteriPen if you're a hiker.

                              My only concern about using this is that...

                              My only concern about using this is that it doesn't kill water-bourne parasites. Would, say, straining the water with a clean cloth before purifying it take care of the parasites, or would they still be a problem?

                              How doees this thing work??? I have the...

                              How doees this thing work??? I have the Seetwater System by MSR, but I always lug extra filters and such. This says it has a 4.0L capacity, what does that mean, it is too small to hold that much, I am new to these types of devices as is painfully clear !! Please Help!!!

                              Best Answer

                              Hopefully this will help. The MIOX stands for Mixed Oxidants and is essentially a very small chemical factory you hold in your hand. The chemical it produces (using salt, water, and electricity) is incredibly effective in killing, rendering ineffective, and disabling protozoa, bacteria, viruses, chemicals, and even bad tastes in the water. It is safe to make, treats the container the chemical is put in, and can even be used as a topical agent for irrigating wounds!

                              The process is done by, first, unscrewing the cap, filling up the tiny chamber on the unit (not the lid) with water (making sure there is enough salt, any kind of salt, in the lid), screwing the cap back on, shaking the unit thus mixing the salt and water, removing the cap again, pushing the button on the side which is determined by the amount of water needing to be treated, waiting until the water stops fizzing, and, once it's stopped, dumping the contents into the water container. Next you let it sit for about 20 minutes (for everything except chryptospiridium) or 4 hours for chrypto. It is really one of the easiest, safest ways of treating water in the backcountry.

                              Hey Cory Guru, I see that this unit could...

                              Hey Cory Guru,

                              I see that this unit could use 3.6v rechargeable lithium batteries. Where do I find the year it is made and serial number???


                              Tucked inside the battery compartment there should be a white sticker with its serial. Those with numbers starting with a 1 are current and compatible with rechargeables, those with numbers starting with a 0 or older and are NOT.

                              Can this use 3.6 v rechargeable lithium...

                              Can this use 3.6 v rechargeable lithium ion batteries?

                              Can anybody tell me if this (or recomend...

                              Can anybody tell me if this (or recomend a purifyer) that kills Leptospirosis? It is an infection transmitted to humans by water that has been contaminated urine of an infected animal. A high danger in the river and stream water in Hawaii (and I would think other tropical areas).

                              where was this thing manufactured and where...

                              where was this thing manufactured and where does its parts come from? i want nothing from china !!

                              these are made In the usa their factory is in Albuquerque New Mexico
                              These were made and used for our military for many years before being introduced for civilian use. The company also makes large water disinfection systems for public utility use. (the water you drink from the tap in your city)

                              How long would a person be able to drink...

                              How long would a person be able to drink the water treated like this?

                              Best Answer

                              I would say that depends on the person, I know people who have lived in the NW for years and never contract giardia because they have developed a stronger tolerance after many years of drinking stream water. That being said, here is some info that may help, found this a while back and dug it out of my delicious bookmark collection.

                              Follow the link for more information, testimonials, etc.

                              Here is some text i pulled from the site.
                              "In contrast to alternative disinfection methods, the safe on-site generation of hypochlorite uses only salt, water, and power as feedstocks. Neither the salt nor the hypochlorite produced is classified as hazardous by the regulatory agencies. The concentration of the generated chlorine solution is below the Hazardous Communications Standard (HCS) safety threshold limit of 1 percent. Although hydrogen gas is evolved from the electrolytic process of on-site generation, automatic venting designs or air dilution systems safely vent this gas to the atmosphere. On-site generation has an excellent safety record, with more than 4,000 units, from a variety of manufacturers, installed worldwide. "

                              They are used for public water disinfection all over the country . The large units they make dissinfect millions of gallons of water a day piped to homes in small to major cities all over the usa and the world. I know because I install them. :)
                              If you live in new mexico your water is more than likely purified by a large miox system

                              So, this isn't an instant thing, but...

                              So, this isn't an instant thing, but requires 4 hrs to have all those things removed from 1.05 Gal?

                              What makes this better over tablets?

                              What makes this better over tablets?

                              Best Answer

                              There are a number of things better and some that are not as good. First the better... One of the things about chemicals is the fresher they are, the more potent they are. Because the user is creating the chemical on the spot he/she will have a far more potent chemical than one contained in a pill because of the radical oxidants that linger after it's created. The pill also has a shelf life (about 5 years in it's package). This is never a concern with the MIOX Purifier. MIOX is also a liquid which is more easily dissipated or dissolved in the water than a pill. The chemical produced by the MIOX (MIOX stands for Mixed Oxidants which include carbon dioxide, hydrogen peroxide, hypochlorus acid, etc.) is more effective in ridding it of pathogens and pesticides than the pill which only contains carbon dioxide or iodine. The MIOX solution is also much safer. If, for instance, you where to digest the pill, it would make you pretty sick (think kids). It can also burn your skin if it's wet and exposed to the pill directly. MIOX can be consumed without much adverse effect and it can be exposed to skin without burning. MIOX can also be used to disinfect wounds, clean contaminated vegetables (often found in third world country street markets), adds an anti-microbial coating to the inside of the water container which it treats along with the water, and is as effective, and in certain conditions, more effective, in killing Giardia and Chryptosporidium (much more than idodine). The pill can only treat water. The above reasons make it more versatile than even a pump filter. It has approximately the same dwell time as a carbon dioxide pill as well (app. 30 minutes for Giardia, bacteria, virus', and 4 hours for crypto). MIOX can be used for large quantities of water where a pill is only made for solo use. The MIOX is the only chemical treatment available which can be tested to make sure there is enough chemical added to the water using the included chlorine strips. Over time, MIOX is far less expensive than any other type of water treatment available.

                              Disadvantages include size and weight (pills are much lighter and smaller than the MIOX Purifier). However, you can produce enough chemical to put into a small vial which will last about 9 days if you don't want to take the unit itself (the unit only weighs 3.5 ounces). Pills are less complicated to use in that you only need to drop one in a liter of water. The MIOX does take a little more effort, but it is fool-proof to operate. There is little to go wrong with a pill whereas the MIOX is an electronic piece of equipment. However, you must be sure the pill is not too old.

                              That should give you some things to consider. I personally use the MIOX and found it to be very reliable and easy to use. I have never gotten sick even though I've treated some pretty disgusting water! I have total faith that it works.