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  • MSR - AutoFlow Gravity Filter - One Color

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  • MSR - AutoFlow Gravity Filter - One Color

MSR AutoFlow Gravity Filter

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    • One Color, 2L
      sale $81.95
    • One Color, 4L
      sale $89.95

    7 Reviews


    Let gravity do the work.

    Collect, filter, and store your water in the backcountry with the quick and convenient MSR Autoflow Gravity Filter. This field-cleanable filter lets gravity do the work and cleans nearly two liters of water per minute. The four-liter reservoir holds enough hydration for your whole group, and the adapter end piece fits onto most standard water bottles and reservoirs. It's field cleanable, too, so you can remove all the bacteria, protozoa, and sediment that's been filtered out and have a filter that's good as new in minutes.

    • Gravity filter for easy cleaning of drinking water in nature
    • Filters out bacteria, protozoa, and sediment
    • Quick filtration gets you 1.75-liters per minute
    • Tool-less cleaning makes it easy to clean in the field
    • Filter directly into most any bottle
    • Item #CAS009L

    Tech Specs

    hollow fiber
    Purifying Element
    bacteria & protozoa, sediment
    2L, 4L
    1.75L per minute
    Field Cleanable
    [2L] 8.5 x 15in, [4L] 11.3 x 20in,
    Claimed Weight
    [2L] 10oz, [4L] 11.1oz
    Recommended Use
    hiking, camping, backpacking
    Manufacturer Warranty
    limited 3 years

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Quick and Easy

    • Familiarity: I've put it through the wringer

    This filter is awesome! I have been using this for a couple years and it still is working great. To help make it flow a little faster get the water down the tube to the filter and once the filter is wet it will start flowing a lot faster. Grab the water, hang it up, and let it flow! Then go set up your tent, grab your snacks and relax.

    Gravity! The Best Assistant

    • Familiarity: I've used it once or twice and have initial impressions

    Works well and isn't challenging to use. Make sure to follow instructions carefully and keep this clean and nice. Setup doesn't take long, I can see it being a little less enjoyable if the weather isn't great though. When comparing with other water purification tools like Life Straw and Iodine this is definitely the way to go.

    Water Boy

    • Familiarity: I've put it through the wringer

    This is exactly what you want for Base Camp water needs or for trips with a big group. Myself and 7 others only used this filter out on the Na Pali Coast across 3 days and it was everything we could ever need. Thoroughly impressed with the filtration and how much water you can get in such a short amount of time.

    If you have questions about this filter please reach out!

    Water Boy

    Very good

    • Familiarity: I've put it through the wringer

    Very nice to be able to fill the bag and fill bottles or bladders as needed. Worked great at elk camp for multiple people. One thing to consider is that in freezing temps it really slows down or doesnt work at all until the filter element warms up or is thawed out. Seems obvious but it was not something I had considered for this trip. I’d also consider getting at least one more filter for longer trips with multiple users sharing it. I have no complaints over the function of the product and I didnt end up with any water borne illness or infections after drinkin gallons of back country water.

    good volume to energy expendeture ratio

      MSR's gravity filter helps streamline lightweight backpacking setups and conveniently cuts out time spent pumping water upon making camp.
      MSR's gravity filters have a well-deserved reputation for quality, and while I think that there are a lot of good water filtration systems out there, there aren't many that accommodate such a large volume, and require so little work.

      Very Convenient

      • Familiarity: I've put it through the wringer

      I bought this filter to be used while working for the Forest Service In Idaho. I ended up choosing this filter primarily because I was looking for an alternative to pumping water. I mean does it get any easier than using gravity to filter water? Sign me up.

      I really like the ease of filtering. All you have to do is fill the bag roll the top and hang the bag up in the tree and you are good to go. This bag is definitely really convenient but does have a few downsides.

      To start off it is heavier than other non pump options. The other downside is having a place to hang it up which can be tricky in some environments.

      Overall this is great filter for the right environment.

      Mr. Clean

      • Familiarity: I've used it several times

      I've used pump filters and steripens and then this gravity filter. Life changing. Steripen works about 50% of the time, not worth it. Pump filters are great if you want an arm workout after a hike or are melting snow.

      If you want to filter water for a group of 4 while backpacking, get this. Easy to set up, use, filter, clean. Took a couple tries to get right, and occasionally my dofus friends would get air bubbles in it which slows things down but if you follow the directions, you'll be filtering water with ease in no time.

      Took this on a 3 day backpacking trip through the Enchantments in WA, group of 8 and this was all we used. No one got the runs.