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MSR MIOX Water Purifier
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MSR MIOX Water Purifier

Item # 709012

$139.95

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The MSR MIOX® purifier makes water microbiologically safe using salt and an electrical current. Click on the Video tab to watch how it works.

  • Proprietary patented technology creates a small batch of an oxidant solution which is mixed with your water to destroy microorganisms
  • MSR MIOX uses a chemical reaction called electrolysis to create a powerful disinfectant that will destroy biological contaminants in your water
  • More effective against microorganisms than chlorine or iodine
  • Destroys viruses and bacteria in 15 minutes, giardia in 30 minutes and cryptosporidia in 4 hours
  • Features a safety indicator so you can be sure your treated water is safe to drink
  • Comes with 1 oz. of salt to treat 200+ liters of water; 2 lithium CR123 batteries; 50 test strips; instruction book; reference card; storage bag
  • MSR MIOX is compact, rugged and submersible
  • Purifies water without iodine; no health risk or unpleasant iodine taste

This purifier works by creating a powerful dose of mixed oxidants (MIOX), which is then added to untreated water, inactivating all viruses, bacteria, Giardia and Cryptosporidium (which even iodine doesn't kill). And since the MIOX Purifier needs only common camera batteries and salt to operate, it's maintenance-free, delivering more water, more easily than any purifier ever before. Please note: MSR products can only be shipped to U.S. addresses.

Made in USA.

Item 709012

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MSR MIOX Water Purifier Specs

Specification

Description

Weight(pen only) 3.5 ounces
Dimensions(pen only) 7 x 1.25 x 1 inches
Material(s)Salt
Removes/DestroysProtozoa, bacteria and viruses
OutputNA
Pump forceNA
Pump strokes per literNA
Field cleanableYes

MSR MIOX Water Purifier Customer Reviews

REVIEW SNAPSHOT®

by PowerReviews
MSR MIOX Water Purifier
 
3.8

(based on 32 reviews)

81%

of respondents would recommend this to a friend.

Pros

  • Lightweight (30)
  • Maintenance (22)
  • Easy to clean (21)
  • Good filtration (5)
  • Easy to pump (3)

Cons

  • Filtered water doesn't taste good (5)
  • Poor filtration (5)

Best Uses

  • Backpacking (30)
  • Hiking (23)
  • Day trip (15)
  • Car camping (6)
  • Reviewer Profile:
  • Avid adventurer (23), Casual/ recreational (8)

Reviewed by 32 customers

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Sep

23

2008

(18 of 20 customers found this review helpful)

 
5.0

a must have item!

By coug

from fort bragg, nc

About Me Outdoor Professional

Site Member

Pros

  • Easy to clean
  • Lightweight
  • Low maintenance

Cons

  • Expensive
  • Not a filter

Best Uses

  • Backpacking
  • Day trip
  • Hiking
  • Military

Comments about MSR MIOX Water Purifier:

as an avid outdoor guy who makes his living in the military traveling around the world to places that never, ever have reliable water sources, the MIOX purifier is a must have item. i've gotten extremely sick from bad water sources in the past. if you've ever experienced such problem, you know it's not something you want to play with. i agree with others that i don't worry about the strips. i double dose everything. my MIOX uses batteries and salt rather conservatively. if you're in the military and are always having to make choices on what you're bringing along on any mission, this guy saves weight and space without a doubt. it fits in a camelbak pocket easily. it also works great for an escape and evasion kit. this is definitely must have gear. while it is expensive, its cost is worth the peace of mind of not getting sick. also keep in mind that it's not a filter. if your water source has "crunchies" in it, you'll be drinking those but they're not going to make you sick. but also keep in mind that filters do not rid your water of viruses. only a purifier can do that. the MIOX rids your water of 100% living organisms. go buy one now!

  • Gift:
  • No

Bottom Line Yes, I would recommend this to a friend

(18 of 20 customers found this review helpful)

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Sep

24

2008

(15 of 17 customers found this review helpful)

 
3.0

Warm Weather Only!

By noam

from Dallas, TX

About Me Avid Adventurer

Pros

  • Easy to clean
  • Good filtration
  • Lightweight
  • Low maintenance

Cons

    Best Uses

    • Backpacking

    Comments about MSR MIOX Water Purifier:

    Here's the deal, this thing will have problems if the water you are using is cold. The reason is simple, the rock salt that is used is in this thing has to go in solution. If it is cold it doesn't dissolve enough and it just gives you a red light saying insufficient salt. If you can warm the water up you are ok otherwise it isn't going to work.

    The plastic tab that goes from top to bottom is too short on mine making it way too easy to cross thread the top cover is the only other gripe.

    When it works great, but if the water is below about 45-50 degrees you are going to need to shake this thing a lot or it is going to do nothing.

    • Gift:
    • No

    Bottom Line Yes, I would recommend this to a friend

    (15 of 17 customers found this review helpful)

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    Oct

    13

    2007

    (13 of 13 customers found this review helpful)

     
    4.0

    great for treating large quantities

    By Cliff Rose

    from San Diego

    About Me Avid Adventurer

    Site Member

    Pros

    • Easy to clean
    • Lightweight
    • Low maintenance

    Cons

      Best Uses

      • Backpacking
      • Hiking

      Comments about MSR MIOX Water Purifier:

      I've never owned a filter because they are heavy and a hassle to carry and use. Most chemical treatments have their disadvantages, too. I've settled on the Miox as the best treatment method for me. It's easy to use (I never bother with the strips) and it's great for treating large volumes of water for big groups. Since I often lead groups of 12 on week-long volunteer trail work trips, the Miox is really the only reasonable water treatment method. It does leave a slight chlorine aftertaste in the water, but this dissipates over time and in any case has never been strong enough to bother me. A fresh set of batteries generally lasts most if not all of a hiking season, which for me is about 4-6 weeks in the backcountry, treating water for groups of up to 12 people. I'm not sure how many gallons that is, but it's quite a few. At least 50. Still, it's a good idea to carry a spare set of batteries.

      Bottom Line Yes, I would recommend this to a friend

      (13 of 13 customers found this review helpful)

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      Oct

      22

      2007

      (12 of 23 customers found this review helpful)

       
      1.0

      Product falls short of expectations

      By greenback

      from Boulder, CO

      About Me Avid Adventurer

      Site Member

      Pros

      • Lightweight

      Cons

      • Requires Batteries

      Best Uses

      • Backpacking

      Comments about MSR MIOX Water Purifier:

      I was initially very excited about this product; it is compact, lightweight and when used properly effective against even cryptosporidium. However, after spending several days attempting to purify water with the Miox, I would not recommend this product due to multiple shortcomings. In order to prepare the brine/oxidant mixture that will purify your water, you must have batteries, crystals and pH strips to check that you have properly completed the process. I found the crystals to diminish far more quickly than one would expect from the manufacturer's information. Furthermore, as our trip progressed, the strength of the oxidant became weaker and weaker, requiring more volume to meet the pH indicator test for potability. I would assume that this was in part due to the batteries weakening and the crystals shrinking. I eventually became so fed up that I used iodine for the last day and a half of the trip. I found function of the Miox dependent on too many factors, making it inconsistent and more hassle than it is worth.

      Bottom Line No, I would not recommend this to a friend

      (12 of 23 customers found this review helpful)

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      Aug

      30

      2007

      (12 of 12 customers found this review helpful)

       
      4.0

      A Versatile Solution

      By Joseph

      from The Mountains of Utah

      About Me Avid Adventurer

      Site Member

      Pros

      • Easy to clean
      • Lightweight
      • No Maintenance
      • Water Fast

      Cons

        Best Uses

        • Backpacking
        • Car Camping
        • Day trip
        • Hiking
        • Travel

        Comments about MSR MIOX Water Purifier:

        I did all the research and went back and forth as to what would serve me best in a variety of situations. I bought this over a year ago and couldn't be more pleased with it. I wanted something that didn't take much room, was light, and would work for backpacking and travel to places where the water is questionable to say the least. I decided on the MIOX because it was smaller and lighter than a filter system, with no chance of getting clogged or having to maintain it. I also decided against the UV option because it will not work if the water is dirty and the light can't penetrate (now I don't like to drink murky water, but if I had to the MIOX would actually ensure it was virus and microbe free). So long story short, it has worked wonderfully. You do need to hit the bottom of it down on to your hand to get the salt water past the screen, but it is not a real detraction. It works much faster than sitting and filtering water forever, and it leaves little to no taste (I only detect a faint taste if I over treat the water, but if I let it sit overnight, i.e. in a camelbak, there is no taste in the morning). All this said, it isn't for everyone. Nevertheless, it a very good solution for many.

        Bottom Line Yes, I would recommend this to a friend

        (12 of 12 customers found this review helpful)

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        Jan

        14

        2009

        (8 of 13 customers found this review helpful)

         
        2.0

        Good if counting ounces

        By Brent Miller

        from San Diego

        About Me Avid Adventurer

        Site Member

        Pros

        • Easy to clean
        • Easy to pump
        • Lightweight
        • Low maintenance

        Cons

        • Filtered water doesn't taste good
        • Poor filtration

        Best Uses

        • Backpacking
        • Day trip
        • Hiking

        Comments about MSR MIOX Water Purifier:

        I've used this on about 10 week long backpacking trips and some weekend trips. Sometimes it works great - when it is warm. When it is cold it takes 2-5 tries to get enough oxidant and you end up using a lot of test strips. Also, it obviously isn't good for dirty/murky/smelly water. And like any chemical treatment you must wait 30 minutes before you can drink. The water tastes like chlorine.

        • Gift:
        • No

        Bottom Line No, I would not recommend this to a friend

        (8 of 13 customers found this review helpful)

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        Sep

        12

        2007

        (8 of 8 customers found this review helpful)

         
        5.0

        Good for the Solo Hiker too

        By Leaves No Trace

        from Richwood, KY

        About Me Long distance hiker

        Site Member

        Pros

        • Easy to clean
        • Easy to pump
        • Fast
        • Lightweight
        • Low maintenance

        Cons

        • Batteries

        Best Uses

        • Backpacking
        • Hiking

        Comments about MSR MIOX Water Purifier:

        I bought this for a long distance hike on the AT. I must say the test strips are difficult to use, but are not strictly required. The instruction pamphlet lists an "overkill option" of overdosing the water by 8X This means using the 4L option twice for each liter. I would treat water for the next day before turning in for the night, and the chlorine taste would be gone in the morning.
        The unit did suck down batteries far in excess of the manufactures guidelines using the overkill option, and in cold weather it takes even more juice out of the batteries. I was able to find CR123 rechargeable batteries, and they lasted the 10 days or so between resupplies. This would be a great way to do multi-week hikes.

        Added bonuses to using the unit:
        It is a good hand sanitizer, especially if you splash the water on your hands when rinsing the water bottle threads. It also serves replacement for washing that water bottle. We've all had the Nalgeene funk from Kool-aid etc in our bottles, and this does a good job at combating that. I use this to clean my pump filter when I take that instead (usually in the winter - who wants wet hands in the cold?).

        In short, I really recommend this product.

        Bottom Line Yes, I would recommend this to a friend

        (8 of 8 customers found this review helpful)

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        Jul

        15

        2008

        (7 of 7 customers found this review helpful)

         
        5.0

        Works Perfectly

        By Tom_scout

        from Columbus, IN

        About Me Avid Adventurer

        Site Member

        Pros

        • Easy to clean
        • Lightweight
        • Low maintenance

        Cons

          Best Uses

          • Backpacking
          • Hiking

          Comments about MSR MIOX Water Purifier:

          The Miox purifier has consistently lived up to its promise. It's simple and reliable. We use it to purify large quantities of water and it works superbly. I agree with others that it's often easier to just double to dose and forget about the test strips. Battery life has been great. I mainly use it with a crew of 12 scouts on multi-day backpacking trips, and we've found it to work really well.

          Bottom Line Yes, I would recommend this to a friend

          (7 of 7 customers found this review helpful)

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          Dec

          9

          2007

          (7 of 7 customers found this review helpful)

           
          4.0

          It works

          By wing it

          from Des Moines, IA

          About Me Casual/ Recreational

          Pros

          • Compact
          • Easy to clean
          • Low maintenance

          Cons

          • Comparatively heavy
          • Not spring water quality

          Best Uses

          • Hiking

          Comments about MSR MIOX Water Purifier:

          I've used this Miox for many, many miles. Many. The disadvantages are that it won't filter out crud - you need a bandana for that. It will taste a little like chlorine. It is also heavier than a half empty Aqua Mira, or an eyedropper of bleach.

          To it's advantage, its weight plus extra batteries (not including salt), is about the same weight as new Aqua Mira. It is small. The parts are easy to find. And, you can double, or even triple, treat your water, if you're so inclined. It does kill everything, too - eventually (4 hours is the usual safety window for the worst of them). So, I was able to leave my water overnight if it was particularly nasty, and feel fine about drinking it by morning. Never had any problems with temperature, like was mentioned in another review. Basic, food grade rock salt works best (though, any salt works, even that stuff you put on your driveway, or just those restaurant packets, if you're not so daring). It's quick, easy, and works. What more could a backpacker want?

          If only it were lighter, and didn't leave the hint of chlorine. Those are my complaints. This thing's been with me 4600 some miles, and I'll carry it with me again.

          Bottom Line Yes, I would recommend this to a friend

          (7 of 7 customers found this review helpful)

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          Sep

          12

          2007

          (5 of 5 customers found this review helpful)

           
          4.0

          A Solid choice

          By Oregon hiker

          from Portland, OR

          About Me Casual/ Recreational

          Pros

          • Lightweight

          Cons

          • Half hour wait time

          Best Uses

          • Backpacking
          • Hiking

          Comments about MSR MIOX Water Purifier:

          I have had the MIOX for a year and a half now, and am satisfied with its performance. I think it is the best option for chemically treating water. Although treated water carries a faint chlorine smell, there is almost no foul taste (a welcome change from iodine). Weight and relative ease of use are the MIOX's chief advantages. Disadvantages (aside from the price) are the half hour treatment time and imperfect mixing with salt crystals that sometimes requires multiple attempts to create the right cocktail. If you also use the test strips included in the package (I don't as I am rarely all that worried about the water I drink) purifying water becomes somewhat time consuming, if not as aggravating as using a pump. Still, nothing is perfect, and the MIOX is a solid choice.

          Bottom Line Yes, I would recommend this to a friend

          (5 of 5 customers found this review helpful)

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